imperial.ac.uk

imperial.ac.uk is SSL secured

Free website and domain report on imperial.ac.uk

Last Updated: 24th March, 2021 Update Now
Overview

Snoop Summary for imperial.ac.uk

This is a free and comprehensive report about imperial.ac.uk. The domain imperial.ac.uk is currently hosted on a server located in United Kingdom with the IP address 146.179.40.148, where GBP is the local currency and the local language is English. Imperial.ac.uk is expected to earn an estimated $298 USD per day from advertising revenue. The sale of imperial.ac.uk would possibly be worth $217,635 USD. This figure is based on the daily revenue potential of the website over a 24 month period. Imperial.ac.uk is wildly popular with an estimated 70,495 daily unique visitors. This report was last updated 24th March, 2021.

About imperial.ac.uk

Site Preview: imperial.ac.uk imperial.ac.uk
Title: Imperial College London
Description: Imperial College London is a world-class university with a mission to benefit society through excellence in science, engineering, medicine and business.
Keywords and Tags: education, popular, reference
Related Terms: banco de occidente plaza imperial, imperial, imperial building auckland, imperial hotels london, imperial palace, imperial space force, imperial valley press online, imperial war museum, metric vs imperial, studentvue imperial
Fav Icon:
Age: Over 28 years old
Domain Created: 31st July, 1996
Domain Updated:
Domain Expires:
Review

Snoop Score

4/5 (Excellent!)

Valuation

$217,635 USD
Note: All valuation figures are estimates.

Popularity

High
Note: Popularity is estimated.

Rank, Reach and Authority

Alexa Rank: 17,385
Alexa Reach:
SEMrush Rank (US):
SEMrush Authority Score:
Moz Domain Authority: 0
Moz Page Authority: 0

Organic vs Paid (Google Ads)

Traffic

Visitors

Daily Visitors: 70,495
Monthly Visitors: 2,145,646
Yearly Visitors: 25,730,675
Note: All visitors figures are estimates.

Visitors By Country

Revenue

Revenue

Daily Revenue: $298 USD
Monthly Revenue: $9,074 USD
Yearly Revenue: $108,812 USD
Note: All revenue figures are estimates.

Revenue By Country

SEO

Backlinks Analysis (SEMrush)

Top New Follow Links

Top Ranking Keywords (US)

Domain Analysis

Value Length
Domain: imperial.ac.uk 14
Domain Name: imperial 8
Extension (TLD): acuk 4

Page Speed Analysis

Average Load Time: 1.38 seconds
Load Time Comparison: Faster than 64% of sites

PageSpeed Insights

Avg. (All Categories) 76
Performance 80
Accessibility 98
Best Practices 73
SEO 100
Progressive Web App 27
0–49 (Fail) 50–89 (Average) 90–100 (Pass)
URL: http://www.imperial.ac.uk/
Updated: 24th March, 2021

2.58 seconds
First Contentful Paint (FCP)
38%
42%
20%

0.00 seconds
First Input Delay (FID)
99%
0%
1%

Simulate loading on desktop
80

Performance

Indicates how well the page is performing and highlights opportunities where performance may be improved for imperial.ac.uk. This includes details about optimizing page load times which can result in a better user experience.

Metrics

First Contentful Paint — 0.8 s
The time taken for the first image or text on the page to be rendered.
Time to Interactive — 1.6 s
The time taken for the page to become fully interactive.
Total Blocking Time — 30 ms
The total blocking time is the sum of all time periods between First Contentful Paint and Time to Interactive (when task length exceeded 50ms).

Other

First CPU Idle — 1.1 s
The time taken for the page's main thread to be quiet enough to handle input.
Max Potential First Input Delay — 90 ms
Users could experience a delay when interacting with the page.
Estimated Input Latency — 10 ms
The time taken for the page to respond to user input (during the busiest 5 second window of page load). Users are likely to perceive imperial.ac.uk as laggy when the latency is higher than 0.05 seconds.
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High Network RTT (Round Trip Times) can have a large impact on performance. Providing servers geographically closer to the user could improve performance.
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1958.14
19.148
1977.908
12.194
1995.977
6.12
2016.094
10.751
2032.869
21.727
2054.707
11.123
2066.128
26.567
2092.805
22.472
2124.977
72.352
2201.016
7.191
2213.779
10.422
2243.534
36.32
2284.948
7.237
2293.393
16.709
2316.142
7.374
2332.199
6.82
2339.894
32.192
2376.745
5.122
2435.103
31.998
2641.677
5.062
2966.159
9.041
Diagnostics
Below is a collection of useful page vitals.
View Data
Metrics
Below is a collection of metrics.
View Data

Opportunities

Defer offscreen images
Time to Interactive can be slowed down by resources on the page. Imperial.ac.uk should consider lazy-loading offscreen and hidden images.
Minify CSS
Cascading Style Sheets (CSS) files can contribute to network payload sizes. Imperial.ac.uk should consider minifying CSS files.
Minify JavaScript — Potential savings of 9 KiB
JavaScript (JS) files can contribute to network payload sizes and increase script parse times. Imperial.ac.uk should consider minifying JS files.
URL Transfer Size (Bytes) Potential Savings (Bytes)
https://www.googletagmanager.com/gtm.js?id=GTM-PS52
79400
8775
Remove unused CSS — Potential savings of 93 KiB
Dead and/or unused rules in Style Sheets (CSS) can contribute to network payload sizes. Imperial.ac.uk should consider removing dead rules from style sheets and deferring the loading of CSS not used for above-the-fold content.
URL Transfer Size (Bytes) Potential Savings (Bytes)
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
86335
79762
http://www.imperial.ac.uk/assets/website/stylesheets/css/color-themes.1.24.10.css
15824
15824
Remove unused JavaScript — Potential savings of 221 KiB
It is advised to remove unused JavaScript in order to reduce bytes consumed by network activity.
URL Transfer Size (Bytes) Potential Savings (Bytes)
http://www.googletagmanager.com/gtm.js?id=GTM-PS52
347873
75119
http://www.googletagmanager.com/gtag/js?id=G-LME5ZDDFS0&l=dataLayer&cx=c
139443
73563
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
72508
53530
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
35274
24146
Enable text compression
Text-based resources should be served with compression, such as gzip, deflate or brotli.
Preconnect to required origins
Resource hints, such as 'preconnect' or 'dns-prefetch', may assist in establishing early connections to important third-party origins.
Avoid multiple page redirects — Potential savings of 190 ms
Redirects can cause additional delays before the page can begin loading. Imperial.ac.uk should avoid multiple or unnecessary page redirects.
URL Time Spent (Ms)
http://imperial.ac.uk/
190
http://www.imperial.ac.uk/
0
Use video formats for animated content
Large GIFs are inefficient for delivering animated content. It is recommended to use MPEG4/WebM videos for animations and PNG/WebP for static images instead of GIF.
Remove duplicate modules in JavaScript bundles
Ensure that no duplicate JavaScript modules from bundles exist to reduce bytes consumed by network activity.
Avoid serving legacy JavaScript to modern browsers — Potential savings of 12 KiB
Polyfills and transforms enable legacy browsers to use new JavaScript features. For bundled JavaScript it is recommended to adopt a modern script deployment strategy using module/nomodule feature detection. This will reduce the amount of code shipped to modern browsers.
URL Potential Savings (Bytes)
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
12020
https://connect.facebook.net/en_US/fbevents.js
46
Preload Largest Contentful Paint image
It is recommended to preload images used by LCP elements, to improve LCP time.
URL Potential Savings (Ms)
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/18-10-Imperial-Today-and-Podcast-promotion-generic_homepage2--tojpeg_1541498866946_x1.jpg
0

Diagnostics

Avoids enormous network payloads — Total size was 2,587 KiB
Large network payloads can cost users money and are linked to long load times.
URL Transfer Size (Bytes)
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/0000_191111_autumn_library_queens_lawn_001--tojpeg_1583940105577_x1.jpg
368018
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/190110_ambassadors_tower_bridge_001--tojpeg_1583940003078_x1.jpg
298229
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/7Q8A6288--tojpeg_1583940852404_x1.jpg
192565
http://www.imperial.ac.uk/assets/website/images/placeholder/events/events-placeholder_2_eventpanel2018_x2.jpg
129896
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x1.jpg
121053
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
86335
https://www.googletagmanager.com/gtm.js?id=GTM-PS52
79400
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
72508
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
72440
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x05.jpg
63926
Avoids an excessive DOM size — 771 elements
A large DOM (Document Object Model) will increase memory usage, cause longer system calculations as well as costly layout reflows.
Statistic Element Value
Total DOM Elements
771
Maximum DOM Depth
16
Maximum Child Elements
13
Avoid chaining critical requests — 4 chains found
Below is a list of Critical Request Chains, which shows which resources are loaded with a high priority. Imperial.ac.uk should consider reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.
User Timing marks and measures
Make use of the User Timing API to measure an app's real-world performance during key user experiences.
JavaScript execution time — 0.3 s
JavaScript (JS) execution time can be lowered by reducing the time required for parsing, compiling and executing JS. Delivering smaller JS payloads may help with this.
URL Total CPU Time (Ms) Script Evaluation (Ms) Script Parse (Ms)
http://www.imperial.ac.uk/
151.069
3.397
1.28
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
139.659
33.909
2.543
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
135.32
130.767
1.688
https://browser.sentry-cdn.com/5.29.0/bundle.min.js
99.224
84.01
3.258
Unattributable
93.41
1.474
0.21
Minimizes main-thread work — 0.9 s
Main-thread work timing can be lowered by reducing the time required for parsing, compiling and executing JS. Delivering smaller JS payloads may help with this.
Category Time Spent (Ms)
Script Evaluation
382.505
Style & Layout
157.808
Other
132.872
Rendering
70.471
Parse HTML & CSS
66.198
Script Parsing & Compilation
33.841
Garbage Collection
7.361
Keep request counts low and transfer sizes small — 71 requests • 2,587 KiB
It is advised to add a budgets.json file in order to set budgets for the quantity and size of page resources.
Resource Type Requests Transfer Size (Bytes)
Total
71
2649369
Image
38
1987510
Script
9
340448
Font
5
184597
Stylesheet
3
104759
Document
3
23305
Other
13
8750
Media
0
0
Third-party
24
285892
Minimize third-party usage — Third-party code blocked the main thread for 10 ms
It is advised to either limit, remove or delay the loading of redundant third-party code which may be significantly impacting load performance.
Third-Party Transfer Size (Bytes) Main-Thread Blocking Time (Ms)
20356
6.164
134377
0
98658
0
20058
0
4502
0
3348
0
1540
0
678
0
Lazy load third-party resources with facades
Consider replacing third-party embeds with a facade until they are required (use lazy loading).
Largest Contentful Paint element — 1 element found
The element which was identified as the Largest Contentful Paint.
Element
Avoid large layout shifts — 5 elements found
Below is a list of all DOM elements that contribute to the CLS of the page.
Element CLS Contribution
0.20215346216731
0.065358772588313
0.014383369319653
0.011097957541522
0.0084807473954724
Uses passive listeners to improve scrolling performance
Improve the page's scroll performance by marking touch and wheel event listeners as 'passive'.
Avoids `document.write()`
Avoid or limit the use of external scripts that are dynamically injected via 'document.write()' as users on slow connections will be delayed by tens of seconds.
Avoid long main-thread tasks — 2 long tasks found
Below is a list of the longest tasks on the main thread, which is useful when identifying the worst input delay contributors.
URL Start Time (Ms) Duration (Ms)
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
1990
93
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
2083
72
Avoid non-composited animations
It is recommended to avoid non-composited animations which are often janky and increase CLS.

Budgets

Performance budget
It is advised to keep the quantity and size of all network requests under the targets set by the provided performance budget.
Timing budget
It is advised to set a timing budget to monitor the performance of your site.

Metrics

Speed Index — 2.0 s
The time taken for the page contents to be visibly populated.
Largest Contentful Paint — 2.1 s
The timing of the largest text or image that is painted.

Other

First Meaningful Paint — 1.1 s
The time taken for the primary content of the page to be rendered.

Opportunities

Eliminate render-blocking resources — Potential savings of 340 ms
Resources, such as JavaScript and style sheets, can block the first paint of the page. Imperial.ac.uk should consider delivering critical JavaScript/style sheets (JS/CSS) inline and deferring all non-critical JS/CSS.
URL Transfer Size (Bytes) Potential Savings (Ms)
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
86335
270
http://www.imperial.ac.uk/assets/website/stylesheets/css/color-themes.1.24.10.css
15824
150
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
31477
190
Properly size images — Potential savings of 293 KiB
Images can slow down the page's load time. Imperial.ac.uk should consider serving more appropriate-sized images.
URL Resource Size (Bytes) Potential Savings (Bytes)
http://www.imperial.ac.uk/assets/website/images/placeholder/events/events-placeholder_2_eventpanel2018_x2.jpg
129416
126095
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
71896
64688
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x1.jpg
120510
26817
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/lcp_1611683980352_eventpanel2018_x1.webp
17694
15878
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x1.jpg
19669
11864
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/18-10-Imperial-Today-and-Podcast-promotion-generic_homepage2--tojpeg_1541498866946_x1.jpg
45475
10099
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x1.jpg
37869
8747
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x05.jpg
63382
8524
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x05.jpg
55522
7467
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/europe-at-night-from-space-nasa-tojpeg-1552495425942-x1_1607945350182_x1.jpg
31073
7178
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x05.jpg
51747
6959
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x05.jpg
41626
5598
Efficiently encode images — Potential savings of 488 KiB
Unoptimized images can consume more cellular data than what is necessary.
URL Resource Size (Bytes) Potential Savings (Bytes)
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x05.jpg
63382
43722
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x05.jpg
55522
38057
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x05.jpg
51747
36510
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/0000_191111_autumn_library_queens_lawn_001--tojpeg_1583940105577_x1.jpg
367473
36341
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/190110_ambassadors_tower_bridge_001--tojpeg_1583940003078_x1.jpg
297684
36286
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/7Q8A6288--tojpeg_1583940852404_x1.jpg
192020
34579
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/imp_130820_campus1_lib_008--tojpeg_1417607683035_x2--tojpeg_1417682075073_x1.jpg
50152
33971
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Impact--tojpeg_1417606493780_x1.jpg
43630
31256
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x05.jpg
41626
29904
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/181101_natwilai_pae_drone_entrepreneur_031-%281%29--t_1542107706895_x1--tojpeg_1557236663888_x1.jpg
41446
29788
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Mega-menu-White-City-Campus-image--tojpeg_1493969367737_x1.jpg
40470
26344
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x1.jpg
120510
22720
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/ICL_Graduation_406--t_1417616392639_x2--tojpeg_1549642146125_x1.jpg
32980
21995
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/IT-survey1--tojpeg_1525171251932_x1.jpg
32891
20870
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Student-blogs--tojpeg_1514904013265_x1.jpg
32477
20102
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x1.jpg
37869
16526
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/15-02-ImperialPodcast_banner_4--tojpeg_1431608741948_x1.jpg
19720
13771
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x1.jpg
19669
6491
Preload key requests — Potential savings of 470 ms
Key requests can be preloaded by using '<link rel=preload>'. Imperial.ac.uk should consider using '<link rel=preload>' to prioritize fetching resources that are currently requested later in page load.
URL Potential Savings (Ms)
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Medium.woff2
470
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Italic.woff2
350

Diagnostics

Serve static assets with an efficient cache policy — 5 resources found
Imperial.ac.uk can speed up repeat visits by increasing the cache lifetime, which is essentially how long before a cached copy expires.
URL Cache TTL (Ms) Transfer Size (Bytes)
https://p.adsymptotic.com/d/px/?_pid=16218&_psign=0aa5badf92527f7732e22463d6fa4dbc&coopa=0&gdpr=0&gdpr_consent=&_puuid=b6b44d0f-6a01-46ae-83ec-09450ead2309&_expected_cookie=fe0963df81f840d16dce60c1734663a4
0
708
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
1200000
72508
https://connect.facebook.net/en_US/fbevents.js
1200000
25524
http://www.google-analytics.com/analytics.js
7200000
19437
https://snap.licdn.com/li.lms-analytics/insight.min.js
17099000
2169

Metrics

Cumulative Layout Shift — 0.313
Cumulative Layout Shift is the measurement of visible elements collective movement within the viewport.
View Data

Opportunities

Serve images in next-gen formats — Potential savings of 917 KiB
Image formats like PNG and JPEG have poor compression when compared to other next-gen formats, such as JPEG 200, JPEG XR and WebP.
URL Resource Size (Bytes) Potential Savings (Bytes)
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/190110_ambassadors_tower_bridge_001--tojpeg_1583940003078_x1.jpg
297684
117648
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/0000_191111_autumn_library_queens_lawn_001--tojpeg_1583940105577_x1.jpg
367473
114911
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/7Q8A6288--tojpeg_1583940852404_x1.jpg
192020
105876
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x1.jpg
120510
71046
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x05.jpg
63382
49586
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x05.jpg
55522
43802
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x05.jpg
51747
41559
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/imp_130820_campus1_lib_008--tojpeg_1417607683035_x2--tojpeg_1417682075073_x1.jpg
50152
37536
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Impact--tojpeg_1417606493780_x1.jpg
43630
34762
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x05.jpg
41626
34652
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/181101_natwilai_pae_drone_entrepreneur_031-%281%29--t_1542107706895_x1--tojpeg_1557236663888_x1.jpg
41446
33314
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
71896
30086
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Mega-menu-White-City-Campus-image--tojpeg_1493969367737_x1.jpg
40470
29458
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/18-10-Imperial-Today-and-Podcast-promotion-generic_homepage2--tojpeg_1541498866946_x1.jpg
45475
28427
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/ICL_Graduation_406--t_1417616392639_x2--tojpeg_1549642146125_x1.jpg
32980
25378
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/IT-survey1--tojpeg_1525171251932_x1.jpg
32891
25315
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x1.jpg
37869
25289
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Student-blogs--tojpeg_1514904013265_x1.jpg
32477
23901
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/15-02-ImperialPodcast_banner_4--tojpeg_1431608741948_x1.jpg
19720
16552
http://www.imperial.ac.uk/assets/website/images/common/hatch-light.png
15389
15281
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x1.jpg
19669
12553
http://www.imperial.ac.uk/assets/website/images/banner/triangle-overlay.png
27493
12001
http://www.imperial.ac.uk/assets/website/images/banner/triangle-overlay-right.png
24795
10505
Reduce initial server response time — Root document took 600 ms
It is advised to keep the server response time short for the main document, because all other requests depend on it.
URL Time Spent (Ms)
http://www.imperial.ac.uk/
604.001

Diagnostics

Ensure text remains visible during webfont load
Make use of the font-display CSS feature, which will ensure text is user-visible while webfonts are loading.
URL Potential Savings (Ms)
http://www.imperial.ac.uk/assets/website/fonts/icons/fonts/imperial-icons.woff?vrmf2d
369.94800018147
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Regular.woff2
452.7039998211
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Bold.woff2
276.34999994189
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Medium.woff2
350.20500002429
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Italic.woff2
462.32100017369
Image elements do not have explicit `width` and `height`
Reduce layout shifts and improve CLS by setting explicit width and height properties on image elements.
URL Failing Elements
http://www.imperial.ac.uk/assets/website/images/placeholder/events/events-placeholder_2_eventpanel2018_x2.jpg
img
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x1.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x05.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x05.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x05.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/18-10-Imperial-Today-and-Podcast-promotion-generic_homepage2--tojpeg_1541498866946_x1.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x05.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x1.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/europe-at-night-from-space-nasa-tojpeg-1552495425942-x1_1607945350182_x1.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x1.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/lcp_1611683980352_eventpanel2018_x1.webp
img
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616514117115_collegeheader2017_x1.webp
img
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616534487742_collegeheader2017_x1.webp
img
98

Accessibility

Indicates how accessible the page is and highlights opportunities where the page can be made more accessible to users of imperial.ac.uk. This includes details about various page attributes that can be optimized.

Navigation

`[accesskey]` values are unique
Access keys assist users with focusing on different parts of the page. Each access key should be unique for proper navigation.
The page contains a heading, skip link, or landmark region
It is advised to provide ways to bypass repetitive content, allowing users to navigate the page efficiently.
`[id]` attributes on active, focusable elements are unique
Ensure all focusable elements have a unique id value to allow them to be visible to users of assistive technologies, like a screen reader.
Heading elements appear in a sequentially-descending order
Properly order all headers and do not skip heading levels to better the navigation and readability for users of assistive technologies, like a screen reader.
No element has a `[tabindex]` value greater than 0
Although technically valid, a tabindex value greater than 0 often creates frustrating experiences for users who rely on assistive technologies.

ARIA

`[aria-*]` attributes match their roles
Avoid mismatching 'aria-*' attributes and their 'role' value, as it invalidates the attribute.
`button`, `link`, and `menuitem` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
`[aria-hidden="true"]` is not present on the document `<body>`
If aria-hidden=true is set on the document body, assistive technologies, like a screen reader will work inconsistently.
`[aria-hidden="true"]` elements do not contain focusable descendents
Interactive elements within an aria-hidden=true element are unavailable to users of assistive technologies, like a screen reader.
ARIA input fields have accessible names
Generic names are announced to users of assistive technologies, like a screen reader, when an input field does not have an accessible name specified.
ARIA `meter` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
ARIA `progressbar` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
`[role]`s have all required `[aria-*]` attributes
Some ARIA roles have required 'aria-*' attributes, which provide essential information about state and functionality.
Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
Some ARIA parent roles cannot perform their intended functions if specific child roles are not used.
`[role]`s are contained by their required parent element
Some ARIA child roles cannot perform their intended functions if specific parent roles are not used.
`[role]` values are valid
All ARIA roles require valid values to perform their intended functions.
ARIA toggle fields have accessible names
Generic names are announced to users of assistive technologies, like a screen reader, when a toggle field does not have an accessible name specified.
ARIA `tooltip` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
ARIA `treeitem` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
`[aria-*]` attributes have valid values
ARIA attributes cannot be interpreted with invalid values when used by screen readers and other assistive technologies.
`[aria-*]` attributes are valid and not misspelled
ARIA attributes cannot be interpreted with invalid names when used by screen readers and other assistive technologies.
ARIA IDs are unique
Ensure all ARIA ID values are unique to prevent elements from being overlooked by assistive technologies, like a screen reader.

Names and labels

Buttons have an accessible name
Buttons become unusable as they are announced simply as "button" when the button does not have an accessible name, when used by screen readers and other assistive technologies.
Document has a `<title>` element
Search engines, screen reader users and other assistive technology users rely on the title to provide an overview of the page and to help determine if the page is relevant to their search.
No form fields have multiple labels
Having multiple labels for form fields can be confusing to assistive technologies, like a screen reader.
`<frame>` or `<iframe>` elements have a title
Screen reader users and other assistive technology users rely on frame titles to describe the contents of frames.
Image elements have `[alt]` attributes
Provide short and descriptive alternative text where possible on informative elements.
`<input type="image">` elements have `[alt]` text
Input buttons with alternative text assist screen readers and other assistive technology users to understand its purpose.
Form elements have associated labels
Screen readers and other assistive technologies rely on labels to properly announce form controls.
Links have a discernible name
In order to improve the navigation for screen reader and other assistive technology users, use link text that is unique, focusable and discernible.
`<object>` elements have `[alt]` text
It is advised that alt text is used on '<object>' elements in order to provide meaning to screen reader and other assistive technology users, as these technologies are unable to translate non-text content.

Tables and lists

`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
Screen readers and other assistive technologies may produce poor and inaccurate output when definition lists are not properly marked up.
Definition list items are wrapped in `<dl>` elements
In order for screen readers and other assistive technologies to properly announce definition list items ('<dt>' and '<dd>'), they must be wrapped in parent a '<dl>' element.
Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
Use proper list structure to aid screen readers and other assistive technologies.
List items (`<li>`) are contained within `<ul>` or `<ol>` parent elements
In order for screen readers to announce list items, ensure that list items ('<li>') are contained within parent '<ul>' or '<ol>' tags.
Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
Screen readers and other assistive technologies have features to make navigating tables easier. Ensure that '<td>' cells using the headers attribute only refer to other cells in the same table, to improve screen reader user experience.
`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
Screen readers and other assistive technologies have features to make navigating tables easier. Ensure that table headers refer to some set of cells, to improve screen reader user experience.

Internationalization and localization

`<html>` element has a `[lang]` attribute
It is advised to provide a lang attribute so that screen readers and other assistive technologies are guaranteed to announce the page's text correctly. When not provided, the user's default language setting will be used which may cause inaccuracies.
`<html>` element has a valid value for its `[lang]` attribute
Specify a valid BCP 47 language in order to help screen readers and other assistive technologies announce text properly.
`[lang]` attributes have a valid value
Specify a valid BCP 47 language on elements in order to help screen readers and other assistive technologies announce text properly.

Best practices

The document does not use `<meta http-equiv="refresh">`
Pages that refresh automatically cause a poor user experience as focus is directed back to the top of the page unexpectedly.
`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
For users with low vision who rely on screen magnification, ensure that zooming is not disabled.

Audio and video

`<video>` elements contain a `<track>` element with `[kind="captions"]`
Imperial.ac.uk may provide assistance to deaf or hearing-impaired users with captions on videos.

Contrast

Background and foreground colors do not have a sufficient contrast ratio.
Many (if not most) users find low-contrast text difficult or impossible to read.
Failing Elements

Manual Checks

The page has a logical tab order
The visual layout should be logical in its tab order and users cannot focus elements that are offscreen.
Interactive controls are keyboard focusable
Ensure that custom interactive controls are keyboard focusable and that a focus indicator is displayed.
Interactive elements indicate their purpose and state
Ensure that interactive elements (such as links and buttons) are distinguishable from non-interactive elements and that they indicate their state.
The user's focus is directed to new content added to the page
When new content (such as a dialogue) is added to the page, the user's focus should be directed to it.
User focus is not accidentally trapped in a region
Avoid focus being accidentally trapped when a user tabs in and out of controls or regions on page.
Custom controls have associated labels
Ensure that custom interactive controls have associated labels, which are provided by aria-label and aria-labelledby attributes.
Custom controls have ARIA roles
Ensure that all custom interactive controls have appropriate ARIA roles.
Visual order on the page follows DOM order
Ensure that the DOM order matches with the page's visual order, in order to improve navigation for screen readers and other assistive technologies.
Offscreen content is hidden from assistive technology
Ensure that offscreen content is hidden through the use of "display:none" styling or the aria-hidden attribute.
HTML5 landmark elements are used to improve navigation
Elements such as <main> and <nav> are recommended as they are used by screen readers and other assistive technologies to improve keyboard navigation.
73

Best Practices

Indicates the recommended, best practices currently in place on the page and highlights the best practices that imperial.ac.uk should incorporate. This includes practices such as protecting pages with HTTPS.

Audits

Avoids requesting the geolocation permission on page load
When requesting a user's location, provide context or consider tying the request to a user action to avoid confusion and mistrust from users.
Avoids requesting the notification permission on page load
When requesting permission to send notifications, provide context or consider tying the request to a user action to avoid confusion and mistrust from users.
Avoids front-end JavaScript libraries with known security vulnerabilities
Ensure that the use of third-party scripts is minimal and that only trusted third-party scripts are used as some may contain known security vulnerabilities which may be exploited by attackers.

Audits

Allows users to paste into password fields
Ensure that password inputs may be pasted into to aid in the user's ability to use password managers and improve security.
Displays images with correct aspect ratio
Ensure that image display dimensions match their natural aspect ratio.
Serves images with appropriate resolution
For maximum image clarity, ensure images have natural dimensions and are proportional to the display size and pixel ratio.
Fonts with `font-display: optional` are preloaded
It is recommended that optional fonts are preloaded.

Audits

Page has the HTML doctype
Ensure a doctype is specified to prevent the browser from switching to quirks-mode.
Properly defines charset
It is advised to declare a character encoding, optionally via a <meta> tag in the first 1024 bytes of the HTML or in the Content-Type HTTP response header.

Audits

Avoids Application Cache
Application cache is deprecated and is no longer recommended.
Detected JavaScript libraries
Below is a list of all front-end JavaScript libraries that were detected on the page.
Name Version
jQuery
3.5.1
Modernizr
3.8.0
FlexSlider
core-js
core-js-pure@3.0.0
Avoids deprecated APIs
Avoid deprecated APIs which will eventually be removed the browser.
Page has valid source maps
Consider deploying source maps for added benefits such as the ability to debug while in production.
URL Map URL
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
http://www.imperial.ac.uk/assets/website/js/build/application.min.js.map
https://browser.sentry-cdn.com/5.29.0/bundle.min.js
https://browser.sentry-cdn.com/5.29.0/bundle.min.js.map
No issues in the `Issues` panel in Chrome Devtools
There may be unresolved issues logged to Chrome Devtools.

Audits

Does not use HTTPS — 52 insecure requests found
Ensure that all pages are protected with HTTPS (including those that do not handle sensitive data) as HTTPS prevents tampering and passive listening on communications between the app and its users. Additionally, HTTPS is a prerequisite for HTTP/2 and many new web platform APIs.
Insecure URL Request Resolution
http://imperial.ac.uk/
Allowed
http://www.imperial.ac.uk/
Allowed
http://www.imperial.ac.uk/assets/website/fonts/icons/fonts/imperial-icons.woff?vrmf2d
Allowed
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Regular.woff2
Allowed
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Bold.woff2
Allowed
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
Allowed
http://www.imperial.ac.uk/assets/website/stylesheets/css/color-themes.1.24.10.css
Allowed
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
Allowed
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616534487742_collegeheader2017_x1.webp
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616514117115_collegeheader2017_x1.webp
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616499842491_collegeheader2017_x1.webp
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/City_of_London_65396749--tojpeg_1417615028107_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/ICL_Graduation_406--t_1417616392639_x2--tojpeg_1549642146125_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/imp_130820_campus1_lib_008--tojpeg_1417607683035_x2--tojpeg_1417682075073_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Impact--tojpeg_1417606493780_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/News--tojpeg_1417606851616_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/181101_natwilai_pae_drone_entrepreneur_031-%281%29--t_1542107706895_x1--tojpeg_1557236663888_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/15-02-ImperialPodcast_banner_4--tojpeg_1431608741948_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/IT-survey1--tojpeg_1525171251932_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Student-blogs--tojpeg_1514904013265_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Lion--tojpeg_1554882885019_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/campus--tojpeg_1416836905639_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Mega-menu-White-City-Campus-image--tojpeg_1493969367737_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/18-10-Imperial-Today-and-Podcast-promotion-generic_homepage2--tojpeg_1541498866946_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/europe-at-night-from-space-nasa-tojpeg-1552495425942-x1_1607945350182_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/lcp_1611683980352_eventpanel2018_x1.webp
Allowed
http://www.imperial.ac.uk/assets/website/images/placeholder/events/events-placeholder_2_eventpanel2018_x2.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/0000_191111_autumn_library_queens_lawn_001--tojpeg_1583940105577_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/190110_ambassadors_tower_bridge_001--tojpeg_1583940003078_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/7Q8A6288--tojpeg_1583940852404_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x05.jpg
Allowed
http://www.imperial.ac.uk/assets/website/stylesheets/css/print.1.24.10.css
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x05.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x05.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x05.jpg
Allowed
http://www.googletagmanager.com/gtm.js?id=GTM-PS52
Allowed
http://www.imperial.ac.uk/assets/website/images/banner/triangle-overlay.png
Allowed
http://www.imperial.ac.uk/assets/website/images/common/hatch-grey.png
Allowed
http://www.imperial.ac.uk/assets/website/images/banner/triangle-overlay-right.png
Allowed
http://www.imperial.ac.uk/assets/website/images/sprite/logo-footer.png
Allowed
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Medium.woff2
Allowed
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Italic.woff2
Allowed
http://www.imperial.ac.uk/assets/website/images/common/hatch-light.png
Allowed
http://www.googletagmanager.com/gtag/js?id=G-LME5ZDDFS0&l=dataLayer&cx=c
Allowed
http://www.google-analytics.com/analytics.js
Allowed
http://9752811.fls.doubleclick.net/activityi;src=9752811;type=phdsc20;cat=allpgrt;ord=1;num=1533062265396;gtm=2wg3h0;auiddc=2122829045.1616608811;~oref=http%3A%2F%2Fwww.imperial.ac.uk%2F?
Allowed
http://9752811.fls.doubleclick.net/activityi;dc_pre=COvSrI_Bye8CFUOghwodRM8E2g;src=9752811;type=phdsc20;cat=allpgrt;ord=1;num=1533062265396;gtm=2wg3h0;auiddc=2122829045.1616608811;~oref=http%3A%2F%2Fwww.imperial.ac.uk%2F?
Allowed

Audits

Registers an `unload` listener
The 'unload' event does not fire reliably, causing issues with browser optimizations such as the Back-Forward Cache. It is recommended that 'pagehide' or 'visibilitychange' events are used instead.
Source
Browser errors were logged to the console
Below is a list of all errors logged to the console, which indicate unresolved problems on the site.
Source Description
Failed to load resource: net::ERR_BLOCKED_BY_CLIENT.Inspector
Failed to load resource: net::ERR_BLOCKED_BY_CLIENT.Inspector
100

SEO

Indicates how well the page is optimized for ranking in search engines and highlights Search Engine Optimization (SEO) opportunities for imperial.ac.uk. This includes optimizations such as providing meta data.

Mobile Friendly

Has a `<meta name="viewport">` tag with `width` or `initial-scale`
It is advised to use a '<meta name="viewport">' tag for the optimization of imperial.ac.uk on mobile screens.
Document uses legible font sizes
Font sizes of 12px or less are too small to most mobile users without user gestures and further action. Aim for more than 60% of page text to use font sizes greater than 12px.
Tap targets are sized appropriately
Interactive elements (such as buttons and links) should be appropriately spaced, sized and easy enough to select or tap with regard to their surrounding elements.

Content Best Practices

Document has a `<title>` element
Search engines, screen reader users and other assistive technology users rely on the title to provide an overview of the page and to help determine if the page is relevant to their search.
Document has a meta description
Meta descriptions may be used by search engines when displaying a link to the page and should concisely summarize the page's content.
Links have descriptive text
Make use of descriptive link text to assist search engines in understanding the content.
Image elements have `[alt]` attributes
Provide short and descriptive alternative text where possible on informative elements.
Document has a valid `hreflang`
Search engines can be instructed to list specific versions of a page for a given language or region through the use of hreflang links.
Document has a valid `rel=canonical`
Search engines can be suggested which URL should be shown in search results through the use of canonical links.
Document avoids plugins
The content of plugins cannot be indexed by search engines and many devices either restrict or do not support them.

Crawling and Indexing

Page has successful HTTP status code
Avoid pages with unsuccessful HTTP status codes as they may not be indexed by search engines.
Links are crawlable
Ensure that the 'href' attribute of anchor elements links to the appropriate destination. This allows for more pages of the site to be discovered by search engines.
Page isn’t blocked from indexing
Pages that cannot be crawled by search engines cannot be indexed or included in their search results. Ensure that search engines have permission to crawl all pages that should be indexed.
robots.txt is valid
Malformed robots.txt files prevent crawlers from understanding how a site wants to be crawled or indexed, which can be devastating to SEO.

Manual Checks

Structured data is valid
Structured data can be validated through the use of the Structured Data Testing Tool and the Structured Data Linter.
27

Progressive Web App

Indicates how valid the aspects of a Progressive Web App (PWA) are for the page and highlights opportunities to enable/improve the PWA of imperial.ac.uk. This includes details about web app manifests.

PWA Optimized

Content is sized correctly for the viewport
Ensure that the width of the app's content matches the width of the viewport, otherwise the app might not be optimized for mobile screens.
Has a `<meta name="viewport">` tag with `width` or `initial-scale`
It is advised to use a '<meta name="viewport">' tag for the optimization of imperial.ac.uk on mobile screens.
Provides a valid `apple-touch-icon`
iOS users of Progressive Web Apps will benefit from an apple touch icon, which can be defined with 'apple-touch-icon', which must point to a non-transparent 192px (or 180px) square PNG.

Installable

Web app manifest or service worker do not meet the installability requirements — 1 reason
User engagement may be increased by leveraging the browsers ability to proactively prompt users to add the app to their homescreen.
Failure reason
No manifest was fetched

PWA Optimized

Does not register a service worker that controls page and `start_url`
A service worker is used to provide Progressive Web Apps the use of features such as working offline, the ability for the app to be added to the homescreen as well as push notifications.
Does not redirect HTTP traffic to HTTPS
It is advised to redirect all HTTP traffic to HTTPS, in order to enable secure web features for all users.
Is not configured for a custom splash screen
Themed splash screens ensure a high-quality user experience at launch for app users.
View Data
Does not set a theme color for the address bar.
A theme may be applied to the browser address bar, which ideally can be made to match the site.
View Data
Manifest doesn't have a maskable icon
Maskable icons are great to ensure that images fill the entire shape when installing the app on a device.

Manual Checks

Site works cross-browser
Ensure that the Progressive Web App works correctly across every major browser.
Page transitions don't feel like they block on the network
Users perceive apps with responsive, snappy transitions as higher peforming and ensures a great user experience, even on a slow network.
Each page has a URL
Ensure that all pages are deep linkable via URL. They should also be unique for the purpose of shareability on social media.
Avg. (All Categories) 62
Performance 34
Accessibility 72
Best Practices 73
SEO 97
Progressive Web App 33
0–49 (Fail) 50–89 (Average) 90–100 (Pass)
URL: http://www.imperial.ac.uk/
Updated: 24th March, 2021

3.39 seconds
First Contentful Paint (FCP)
27%
43%
30%

0.02 seconds
First Input Delay (FID)
97%
2%
1%

Simulate loading on mobile
34

Performance

Indicates how well the page is performing and highlights opportunities where performance may be improved for imperial.ac.uk. This includes details about optimizing page load times which can result in a better user experience.

Opportunities

Defer offscreen images — Potential savings of 104 KiB
Time to Interactive can be slowed down by resources on the page. Imperial.ac.uk should consider lazy-loading offscreen and hidden images.
URL Resource Size (Bytes) Potential Savings (Bytes)
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/imp_130820_campus1_lib_008--tojpeg_1417607683035_x2--tojpeg_1417682075073_x1.jpg
50152
50152
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/ICL_Graduation_406--t_1417616392639_x2--tojpeg_1549642146125_x1.jpg
32980
32980
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/City_of_London_65396749--tojpeg_1417615028107_x1.jpg
11873
11873
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616514117115_collegeheader2017_x2.webp
4918
4918
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616534487742_collegeheader2017_x2.webp
4230
4230
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616499842491_collegeheader2017_x2.webp
2562
2562
Minify CSS
Cascading Style Sheets (CSS) files can contribute to network payload sizes. Imperial.ac.uk should consider minifying CSS files.
Minify JavaScript — Potential savings of 9 KiB
JavaScript (JS) files can contribute to network payload sizes and increase script parse times. Imperial.ac.uk should consider minifying JS files.
URL Transfer Size (Bytes) Potential Savings (Bytes)
https://www.googletagmanager.com/gtm.js?id=GTM-PS52
79400
8775
Enable text compression
Text-based resources should be served with compression, such as gzip, deflate or brotli.
Preconnect to required origins
Resource hints, such as 'preconnect' or 'dns-prefetch', may assist in establishing early connections to important third-party origins.
Initial server response time was short — Root document took 210 ms
It is advised to keep the server response time short for the main document, because all other requests depend on it.
URL Time Spent (Ms)
http://www.imperial.ac.uk/
209.817
Avoid multiple page redirects — Potential savings of 630 ms
Redirects can cause additional delays before the page can begin loading. Imperial.ac.uk should avoid multiple or unnecessary page redirects.
URL Time Spent (Ms)
http://imperial.ac.uk/
630
http://www.imperial.ac.uk/
0
Use video formats for animated content
Large GIFs are inefficient for delivering animated content. It is recommended to use MPEG4/WebM videos for animations and PNG/WebP for static images instead of GIF.
Remove duplicate modules in JavaScript bundles
Ensure that no duplicate JavaScript modules from bundles exist to reduce bytes consumed by network activity.
Avoid serving legacy JavaScript to modern browsers — Potential savings of 12 KiB
Polyfills and transforms enable legacy browsers to use new JavaScript features. For bundled JavaScript it is recommended to adopt a modern script deployment strategy using module/nomodule feature detection. This will reduce the amount of code shipped to modern browsers.
URL Potential Savings (Bytes)
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
12024
https://connect.facebook.net/en_US/fbevents.js
45
Preload Largest Contentful Paint image
It is recommended to preload images used by LCP elements, to improve LCP time.
URL Potential Savings (Ms)
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x2.jpg
0

Diagnostics

Avoids enormous network payloads — Total size was 2,473 KiB
Large network payloads can cost users money and are linked to long load times.
URL Transfer Size (Bytes)
http://www.imperial.ac.uk/assets/website/images/placeholder/events/events-placeholder_4_eventpanel2018_x2.jpg
214132
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/0000_191111_autumn_library_queens_lawn_001--tojpeg_1583940105577_x05.jpg
141991
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x2.jpg
136123
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/190110_ambassadors_tower_bridge_001--tojpeg_1583940003078_x05.jpg
136016
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x2.jpg
105097
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x2.jpg
102061
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/europe-at-night-from-space-nasa-tojpeg-1552495425942-x1_1607945350182_x2.jpg
98155
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/7Q8A6288--tojpeg_1583940852404_x05.jpg
95046
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x4.jpg
91697
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
86458
Avoids an excessive DOM size — 771 elements
A large DOM (Document Object Model) will increase memory usage, cause longer system calculations as well as costly layout reflows.
Statistic Element Value
Total DOM Elements
771
Maximum DOM Depth
18
Maximum Child Elements
14
Avoid chaining critical requests — 4 chains found
Below is a list of Critical Request Chains, which shows which resources are loaded with a high priority. Imperial.ac.uk should consider reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.
User Timing marks and measures
Make use of the User Timing API to measure an app's real-world performance during key user experiences.
Keep request counts low and transfer sizes small — 67 requests • 2,473 KiB
It is advised to add a budgets.json file in order to set budgets for the quantity and size of page resources.
Resource Type Requests Transfer Size (Bytes)
Total
67
2532058
Image
35
1871375
Script
9
339965
Font
5
184583
Stylesheet
3
105029
Document
3
23298
Other
12
7808
Media
0
0
Third-party
23
284393
Lazy load third-party resources with facades
Consider replacing third-party embeds with a facade until they are required (use lazy loading).
Largest Contentful Paint element — 1 element found
The element which was identified as the Largest Contentful Paint.
Element
Avoid large layout shifts — 5 elements found
Below is a list of all DOM elements that contribute to the CLS of the page.
Element CLS Contribution
0.35996705107084
0.32284544892916
0.24559671737973
0.14896799893908
0.10150722854506
Avoids `document.write()`
Avoid or limit the use of external scripts that are dynamically injected via 'document.write()' as users on slow connections will be delayed by tens of seconds.
Avoid long main-thread tasks — 17 long tasks found
Below is a list of the longest tasks on the main thread, which is useful when identifying the worst input delay contributors.
URL Start Time (Ms) Duration (Ms)
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
9136
287
http://www.imperial.ac.uk/
1474
243
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
8970
166
http://www.googletagmanager.com/gtag/js?id=G-LME5ZDDFS0&l=dataLayer&cx=c
10534
159
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
4433
152
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
10693
152
http://www.imperial.ac.uk/
630
138
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
3540
135
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
10901
131
http://www.googletagmanager.com/gtm.js?id=GTM-PS52
4305
128
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
2040
118
http://www.google-analytics.com/analytics.js
10438
96
https://browser.sentry-cdn.com/5.29.0/bundle.min.js
10353
85
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
9426
81
https://connect.facebook.net/en_US/fbevents.js
6115
65
Unattributable
815
57
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
9526
54
Avoid non-composited animations — 2 animated elements found
It is recommended to avoid non-composited animations which are often janky and increase CLS.
Element

Budgets

Performance budget
It is advised to keep the quantity and size of all network requests under the targets set by the provided performance budget.
Timing budget
It is advised to set a timing budget to monitor the performance of your site.

Other

Network Requests
Below is a list of network requests that were made during page load.
URL Protocol Start Time (Ms) End Time (Ms) Transfer Size (Bytes) Resource Size (Bytes) Status Code MIME Type Resource Type
http://imperial.ac.uk/
http/1.1
0
209.53899994493
358
0
301
text/html
http://www.imperial.ac.uk/
http/1.1
215.07899975404
423.90399985015
21537
79793
200
text/html
Document
http://www.imperial.ac.uk/assets/website/fonts/icons/fonts/imperial-icons.woff?vrmf2d
http/1.1
443.76099994406
539.42700009793
12367
11888
200
application/font-woff
Font
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Regular.woff2
http/1.1
443.99800011888
538.32300007343
41917
41436
200
application/font-woff2
Font
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Bold.woff2
http/1.1
444.18499991298
628.19699989632
45040
44560
200
application/font-woff2
Font
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
http/1.1
449.46999987587
724.29900011048
86458
695044
200
text/css
Stylesheet
http://www.imperial.ac.uk/assets/website/stylesheets/css/color-themes.1.24.10.css
http/1.1
449.76399978623
658.78999978304
15948
179836
200
text/css
Stylesheet
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
http/1.1
450.00099996105
635.01700013876
31499
89476
200
text/javascript
Script
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
http/1.1
661.55199985951
759.04100015759
35296
124565
200
text/javascript
Script
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616534487742_collegeheader2017_x2.webp
http/1.1
728.80299994722
916.5900000371
4772
4230
200
image/webp
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616514117115_collegeheader2017_x2.webp
http/1.1
775.81000002101
916.29699990153
5461
4918
200
image/webp
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616499842491_collegeheader2017_x2.webp
http/1.1
775.97900014371
967.565999832
3105
2562
200
image/webp
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/City_of_London_65396749--tojpeg_1417615028107_x1.jpg
http/1.1
776.254999917
872.60799994692
12412
11873
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/ICL_Graduation_406--t_1417616392639_x2--tojpeg_1549642146125_x1.jpg
http/1.1
776.37499989942
883.94800014794
33523
32980
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/imp_130820_campus1_lib_008--tojpeg_1417607683035_x2--tojpeg_1417682075073_x1.jpg
http/1.1
776.55099984258
880.38400001824
50694
50152
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Impact--tojpeg_1417606493780_x1.jpg
http/1.1
776.69700002298
974.3300001137
44173
43630
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/News--tojpeg_1417606851616_x1.jpg
http/1.1
777.39499974996
881.13400014117
15619
15077
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/181101_natwilai_pae_drone_entrepreneur_031-%281%29--t_1542107706895_x1--tojpeg_1557236663888_x1.jpg
http/1.1
777.5599998422
968.77699997276
41987
41446
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/15-02-ImperialPodcast_banner_4--tojpeg_1431608741948_x1.jpg
http/1.1
778.14699988812
972.50799974427
20264
19720
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/IT-survey1--tojpeg_1525171251932_x1.jpg
http/1.1
778.34099996835
986.06800008565
33435
32891
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Student-blogs--tojpeg_1514904013265_x1.jpg
http/1.1
778.4719998017
1161.4769999869
33021
32477
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Lion--tojpeg_1554882885019_x1.jpg
http/1.1
778.65599980578
880.05599984899
10105
9563
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/campus--tojpeg_1416836905639_x1.jpg
http/1.1
778.82200013846
968.57299981639
18154
17612
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Mega-menu-White-City-Campus-image--tojpeg_1493969367737_x1.jpg
http/1.1
778.94400013611
976.67599981651
41013
40470
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/18-10-Imperial-Today-and-Podcast-promotion-generic_homepage2--tojpeg_1541498866946_x05.jpg
http/1.1
779.11299979314
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Image
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http/1.1
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Image
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http/1.1
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Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x4.jpg
http/1.1
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Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/lcp_1611683980352_eventpanel2018_x2.webp
http/1.1
779.76799989119
990.78400013968
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Image
http://www.imperial.ac.uk/assets/website/images/placeholder/events/events-placeholder_4_eventpanel2018_x2.jpg
http/1.1
780.17299994826
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214132
213628
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
http/1.1
780.28899990022
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Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x05.jpg
http/1.1
780.39499977604
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Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/0000_191111_autumn_library_queens_lawn_001--tojpeg_1583940105577_x05.jpg
http/1.1
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Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/190110_ambassadors_tower_bridge_001--tojpeg_1583940003078_x05.jpg
http/1.1
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136016
135472
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Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/7Q8A6288--tojpeg_1583940852404_x05.jpg
http/1.1
781.4790001139
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Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x2.jpg
http/1.1
782.62599976733
1085.7810000889
136123
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200
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Image
http://www.imperial.ac.uk/assets/website/stylesheets/css/print.1.24.10.css
http/1.1
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Stylesheet
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http/1.1
782.73899992928
1006.4909998327
102061
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Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x2.jpg
http/1.1
782.81999984756
1346.1380000226
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104552
200
image/jpeg
Image
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x2.jpg
http/1.1
782.95599995181
1261.6340001114
78714
78170
200
image/jpeg
Image
http://www.googletagmanager.com/gtm.js?id=GTM-PS52
http/1.1
783.58299983665
915.65999994054
311
0
302
text/html
http://www.imperial.ac.uk/assets/website/images/common/hatch-grey.png
http/1.1
821.12800003961
1015.9979998134
1563
1062
200
image/png
Image
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http/1.1
833.30800011754
1027.3019997403
5227
4726
200
image/png
Image
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Medium.woff2
http/1.1
835.70900000632
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42098
41616
200
application/font-woff2
Font
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Italic.woff2
http/1.1
838.80600007251
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200
application/font-woff2
Font
https://www.googletagmanager.com/gtm.js?id=GTM-PS52
h2
916.51699971408
941.92400015891
79400
347873
200
application/javascript
Script
https://browser.sentry-cdn.com/5.29.0/bundle.min.js
h2
1094.2299999297
1114.951999858
20356
64642
200
application/javascript
Script
http://www.googletagmanager.com/gtag/js?id=G-LME5ZDDFS0&l=dataLayer&cx=c
http/1.1
1370.7940001041
1462.1850000694
333
0
302
text/html
http://www.google-analytics.com/analytics.js
http/1.1
1375.8279997855
1385.1279998198
19437
47332
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text/javascript
Script
http://9752811.fls.doubleclick.net/activityi;src=9752811;type=phdsc20;cat=allpgrt;ord=1;num=328558929480;gtm=2wg3h0;auiddc=1600686856.1616608844;~oref=http%3A%2F%2Fwww.imperial.ac.uk%2F?
http/1.1
1407.0219998248
1415.1340001263
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Document
https://connect.facebook.net/en_US/fbevents.js
h2
1419.1529997624
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application/x-javascript
Script
https://snap.licdn.com/li.lms-analytics/insight.min.js
http/1.1
1419.9339998886
1503.1789997593
2169
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Script
https://www.googletagmanager.com/gtag/js?id=G-LME5ZDDFS0&l=dataLayer&cx=c
h2
1463.6269998737
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Script
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h2
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Script
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h2
1553.0119999312
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694
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XHR
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1592.2479997389
1618.8710001297
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0
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Other
https://px.ads.linkedin.com/collect?v=2&fmt=js&pid=406601&time=1616608843762&url=http%3A%2F%2Fwww.imperial.ac.uk%2F
http/1.1
1603.0250000767
1670.9509999491
882
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h2
1609.2710001394
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Image
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h2
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image/gif
Image
https://px.ads.linkedin.com/collect?v=2&fmt=js&pid=406601&time=1616608843762&url=http%3A%2F%2Fwww.imperial.ac.uk%2F&cookiesTest=true
http/1.1
1671.8119997531
1706.1139997095
967
0
302
https://www.linkedin.com/px/li_sync?redirect=https%3A%2F%2Fpx.ads.linkedin.com%2Fcollect%3Fv%3D2%26fmt%3Djs%26pid%3D406601%26time%3D1616608843762%26url%3Dhttp%253A%252F%252Fwww.imperial.ac.uk%252F%26cookiesTest%3Dtrue%26liSync%3Dtrue
http/1.1
1706.7889999598
1757.9879998229
2269
0
302
https://px.ads.linkedin.com/collect?v=2&fmt=js&pid=406601&time=1616608843762&url=http%3A%2F%2Fwww.imperial.ac.uk%2F&cookiesTest=true&liSync=true
http/1.1
1758.92199995
1790.8640000969
541
0
302
https://p.adsymptotic.com/d/px/?_pid=16218&_psign=0aa5badf92527f7732e22463d6fa4dbc&coopa=0&gdpr=0&gdpr_consent=&_puuid=300cc244-cb88-40d7-95c1-18c210fda846
http/1.1
1791.5869997814
1857.4429997243
832
0
302
https://p.adsymptotic.com/d/px/?_pid=16218&_psign=0aa5badf92527f7732e22463d6fa4dbc&coopa=0&gdpr=0&gdpr_consent=&_puuid=300cc244-cb88-40d7-95c1-18c210fda846&_expected_cookie=e5cbbb121014bacee69daccfd46a00c3
h2
1861.3279997371
1924.8049999587
708
43
200
image/gif
Image
https://www.facebook.com/tr/
2194.7789997794
2204.5140000992
0
0
-1
Other
Network Round Trip Times — 0 ms
High Network RTT (Round Trip Times) can have a large impact on performance. Providing servers geographically closer to the user could improve performance.
Server Backend Latencies — 0 ms
High server latencies indicate the server is overloaded or has a poor backend performance.
Tasks
Below is a list of the top-level main thread tasks that executed during page load.
Start Time (Ms) End Time (Ms)
471.521
11.057
483.606
5.406
490.151
5.042
702.873
8.883
769.8
29.543
799.434
33.8
833.264
121.295
968.46
83.093
1053.569
68.845
1130.909
71.87
1207.866
40.57
1248.462
10.082
1273.788
26.879
1317.97
13.716
1333.042
31.915
1372.234
7.06
1379.869
7.331
1387.237
75.931
1470.684
21.355
1492.06
9.481
1504.856
7.961
1517.717
6.07
1531.351
6.917
1539.823
24.023
1564.129
16.346
1599.135
39.684
1639.308
5.043
1650.053
8.957
1674.889
38.023
1714.469
14.325
1970.091
9.686
2210.814
32.75
Diagnostics
Below is a collection of useful page vitals.
View Data
Metrics
Below is a collection of metrics.
View Data

Metrics

First Contentful Paint — 2.6 s
The time taken for the first image or text on the page to be rendered.
Speed Index — 5.0 s
The time taken for the page contents to be visibly populated.

Other

First Meaningful Paint — 3.4 s
The time taken for the primary content of the page to be rendered.
Estimated Input Latency — 80 ms
The time taken for the page to respond to user input (during the busiest 5 second window of page load). Users are likely to perceive imperial.ac.uk as laggy when the latency is higher than 0.05 seconds.
First Contentful Paint (3G) — 4987.5 ms
The time taken for the first image or text on the page to be rendered while on a 3G network.

Opportunities

Remove unused CSS — Potential savings of 93 KiB
Dead and/or unused rules in Style Sheets (CSS) can contribute to network payload sizes. Imperial.ac.uk should consider removing dead rules from style sheets and deferring the loading of CSS not used for above-the-fold content.
URL Transfer Size (Bytes) Potential Savings (Bytes)
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
86458
79793
http://www.imperial.ac.uk/assets/website/stylesheets/css/color-themes.1.24.10.css
15948
15948
Remove unused JavaScript — Potential savings of 220 KiB
It is advised to remove unused JavaScript in order to reduce bytes consumed by network activity.
URL Transfer Size (Bytes) Potential Savings (Bytes)
http://www.googletagmanager.com/gtm.js?id=GTM-PS52
347873
75119
http://www.googletagmanager.com/gtag/js?id=G-LME5ZDDFS0&l=dataLayer&cx=c
139443
73563
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
72531
53547
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
35296
23015

Diagnostics

Serve static assets with an efficient cache policy — 5 resources found
Imperial.ac.uk can speed up repeat visits by increasing the cache lifetime, which is essentially how long before a cached copy expires.
URL Cache TTL (Ms) Transfer Size (Bytes)
https://p.adsymptotic.com/d/px/?_pid=16218&_psign=0aa5badf92527f7732e22463d6fa4dbc&coopa=0&gdpr=0&gdpr_consent=&_puuid=300cc244-cb88-40d7-95c1-18c210fda846&_expected_cookie=e5cbbb121014bacee69daccfd46a00c3
0
708
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
1200000
72531
https://connect.facebook.net/en_US/fbevents.js
1200000
24974
http://www.google-analytics.com/analytics.js
7200000
19437
https://snap.licdn.com/li.lms-analytics/insight.min.js
17067000
2169
Reduce JavaScript execution time — 2.1 s
JavaScript (JS) execution time can be lowered by reducing the time required for parsing, compiling and executing JS. Delivering smaller JS payloads may help with this.
URL Total CPU Time (Ms) Script Evaluation (Ms) Script Parse (Ms)
http://www.imperial.ac.uk/
1250.04
16.28
7.084
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
803.992
700.4
7.664
Unattributable
495.068
7.26
2.016
http://www.googletagmanager.com/gtm.js?id=GTM-PS52
471.056
397.296
55.824
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
303.572
219.78
10.504
https://connect.facebook.net/signals/config/182489349100448?v=2.9.33&r=stable
287.668
255.408
21.252
http://www.googletagmanager.com/gtag/js?id=G-LME5ZDDFS0&l=dataLayer&cx=c
159.908
135.904
18.792
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
118.172
0
0
http://www.google-analytics.com/analytics.js
115.888
103.96
7.48
https://browser.sentry-cdn.com/5.29.0/bundle.min.js
77.068
52.788
6.716
https://connect.facebook.net/en_US/fbevents.js
65.384
54.464
7.724
http://9752811.fls.doubleclick.net/activityi;src=9752811;type=phdsc20;cat=allpgrt;ord=1;num=328558929480;gtm=2wg3h0;auiddc=1600686856.1616608844;~oref=http%3A%2F%2Fwww.imperial.ac.uk%2F?
50.664
5.756
4.12

Metrics

Largest Contentful Paint — 12.1 s
The timing of the largest text or image that is painted.
Time to Interactive — 9.1 s
The time taken for the page to become fully interactive.
Total Blocking Time — 890 ms
The total blocking time is the sum of all time periods between First Contentful Paint and Time to Interactive (when task length exceeded 50ms).
Cumulative Layout Shift — 1.309
Cumulative Layout Shift is the measurement of visible elements collective movement within the viewport.
View Data

Other

First CPU Idle — 7.2 s
The time taken for the page's main thread to be quiet enough to handle input.
Max Potential First Input Delay — 290 ms
Users could experience a delay when interacting with the page.

Opportunities

Eliminate render-blocking resources — Potential savings of 1,010 ms
Resources, such as JavaScript and style sheets, can block the first paint of the page. Imperial.ac.uk should consider delivering critical JavaScript/style sheets (JS/CSS) inline and deferring all non-critical JS/CSS.
URL Transfer Size (Bytes) Potential Savings (Ms)
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
86458
1080
http://www.imperial.ac.uk/assets/website/stylesheets/css/color-themes.1.24.10.css
15948
480
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
31499
630
Properly size images — Potential savings of 255 KiB
Images can slow down the page's load time. Imperial.ac.uk should consider serving more appropriate-sized images.
URL Resource Size (Bytes) Potential Savings (Bytes)
http://www.imperial.ac.uk/assets/website/images/placeholder/events/events-placeholder_4_eventpanel2018_x2.jpg
213628
164526
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x4.jpg
91153
48271
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/lcp_1611683980352_eventpanel2018_x2.webp
50020
38523
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
71896
9711
Efficiently encode images — Potential savings of 435 KiB
Unoptimized images can consume more cellular data than what is necessary.
URL Resource Size (Bytes) Potential Savings (Bytes)
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/0000_191111_autumn_library_queens_lawn_001--tojpeg_1583940105577_x05.jpg
141446
47286
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/190110_ambassadors_tower_bridge_001--tojpeg_1583940003078_x05.jpg
135472
44835
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/7Q8A6288--tojpeg_1583940852404_x05.jpg
94502
37683
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/imp_130820_campus1_lib_008--tojpeg_1417607683035_x2--tojpeg_1417682075073_x1.jpg
50152
33971
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Impact--tojpeg_1417606493780_x1.jpg
43630
31256
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/181101_natwilai_pae_drone_entrepreneur_031-%281%29--t_1542107706895_x1--tojpeg_1557236663888_x1.jpg
41446
29788
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x05.jpg
66106
28959
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Mega-menu-White-City-Campus-image--tojpeg_1493969367737_x1.jpg
40470
26344
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x2.jpg
84508
24190
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/ICL_Graduation_406--t_1417616392639_x2--tojpeg_1549642146125_x1.jpg
32980
21995
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x4.jpg
91153
21333
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/IT-survey1--tojpeg_1525171251932_x1.jpg
32891
20870
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Student-blogs--tojpeg_1514904013265_x1.jpg
32477
20102
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/15-02-ImperialPodcast_banner_4--tojpeg_1431608741948_x1.jpg
19720
13771
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x2.jpg
104552
11665
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x2.jpg
78170
11591
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x2.jpg
101516
10954
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x2.jpg
135579
8876
Serve images in next-gen formats — Potential savings of 769 KiB
Image formats like PNG and JPEG have poor compression when compared to other next-gen formats, such as JPEG 200, JPEG XR and WebP.
URL Resource Size (Bytes) Potential Savings (Bytes)
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/0000_191111_autumn_library_queens_lawn_001--tojpeg_1583940105577_x05.jpg
141446
75546
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/190110_ambassadors_tower_bridge_001--tojpeg_1583940003078_x05.jpg
135472
71548
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/7Q8A6288--tojpeg_1583940852404_x05.jpg
94502
61782
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x4.jpg
91153
60963
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x2.jpg
84508
52748
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x05.jpg
66106
47244
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/imp_130820_campus1_lib_008--tojpeg_1417607683035_x2--tojpeg_1417682075073_x1.jpg
50152
37536
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Impact--tojpeg_1417606493780_x1.jpg
43630
34762
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x2.jpg
104552
33584
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/181101_natwilai_pae_drone_entrepreneur_031-%281%29--t_1542107706895_x1--tojpeg_1557236663888_x1.jpg
41446
33314
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x2.jpg
135579
31579
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
71896
30086
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Mega-menu-White-City-Campus-image--tojpeg_1493969367737_x1.jpg
40470
29458
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/europe-at-night-from-space-nasa-tojpeg-1552495425942-x1_1607945350182_x2.jpg
97613
28707
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x2.jpg
78170
28388
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x2.jpg
101516
26652
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/ICL_Graduation_406--t_1417616392639_x2--tojpeg_1549642146125_x1.jpg
32980
25378
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/IT-survey1--tojpeg_1525171251932_x1.jpg
32891
25315
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Student-blogs--tojpeg_1514904013265_x1.jpg
32477
23901
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/15-02-ImperialPodcast_banner_4--tojpeg_1431608741948_x1.jpg
19720
16552
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/18-10-Imperial-Today-and-Podcast-promotion-generic_homepage2--tojpeg_1541498866946_x05.jpg
20558
12444
Preload key requests — Potential savings of 4,080 ms
Key requests can be preloaded by using '<link rel=preload>'. Imperial.ac.uk should consider using '<link rel=preload>' to prioritize fetching resources that are currently requested later in page load.
URL Potential Savings (Ms)
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Medium.woff2
4080
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Italic.woff2
3630

Diagnostics

Minimize main-thread work — 4.3 s
Main-thread work timing can be lowered by reducing the time required for parsing, compiling and executing JS. Delivering smaller JS payloads may help with this.
Category Time Spent (Ms)
Script Evaluation
1971.636
Other
909.05999999999
Style & Layout
751.992
Parse HTML & CSS
237.252
Rendering
215.552
Script Parsing & Compilation
157.592
Garbage Collection
57.356
Ensure text remains visible during webfont load
Make use of the font-display CSS feature, which will ensure text is user-visible while webfonts are loading.
URL Potential Savings (Ms)
http://www.imperial.ac.uk/assets/website/fonts/icons/fonts/imperial-icons.woff?vrmf2d
95.666000153869
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Regular.woff2
94.324999954551
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Bold.woff2
184.01199998334
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Medium.woff2
185.18400005996
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Italic.woff2
363.4810000658
Reduce the impact of third-party code — Third-party code blocked the main thread for 480 ms
It is advised to either limit, remove or delay the loading of redundant third-party code which may be significantly impacting load performance.
Third-Party Transfer Size (Bytes) Main-Thread Blocking Time (Ms)
134347
304.76
98131
147.188
20058
32.224
20356
0
4438
0
2455
0
1540
0
678
0
Does not use passive listeners to improve scrolling performance
Improve the page's scroll performance by marking touch and wheel event listeners as 'passive'.
Source
Image elements do not have explicit `width` and `height`
Reduce layout shifts and improve CLS by setting explicit width and height properties on image elements.
URL Failing Elements
http://www.imperial.ac.uk/assets/website/images/placeholder/events/events-placeholder_4_eventpanel2018_x2.jpg
img
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x2.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x2.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x2.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/europe-at-night-from-space-nasa-tojpeg-1552495425942-x1_1607945350182_x2.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x4.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x2.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x2.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/lcp_1611683980352_eventpanel2018_x2.webp
img
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/18-10-Imperial-Today-and-Podcast-promotion-generic_homepage2--tojpeg_1541498866946_x05.jpg
72

Accessibility

Indicates how accessible the page is and highlights opportunities where the page can be made more accessible to users of imperial.ac.uk. This includes details about various page attributes that can be optimized.

Navigation

`[accesskey]` values are unique
Access keys assist users with focusing on different parts of the page. Each access key should be unique for proper navigation.
The page contains a heading, skip link, or landmark region
It is advised to provide ways to bypass repetitive content, allowing users to navigate the page efficiently.
`[id]` attributes on active, focusable elements are unique
Ensure all focusable elements have a unique id value to allow them to be visible to users of assistive technologies, like a screen reader.
Heading elements appear in a sequentially-descending order
Properly order all headers and do not skip heading levels to better the navigation and readability for users of assistive technologies, like a screen reader.
No element has a `[tabindex]` value greater than 0
Although technically valid, a tabindex value greater than 0 often creates frustrating experiences for users who rely on assistive technologies.

ARIA

`[aria-*]` attributes match their roles
Avoid mismatching 'aria-*' attributes and their 'role' value, as it invalidates the attribute.
`button`, `link`, and `menuitem` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
`[aria-hidden="true"]` is not present on the document `<body>`
If aria-hidden=true is set on the document body, assistive technologies, like a screen reader will work inconsistently.
`[aria-hidden="true"]` elements do not contain focusable descendents
Interactive elements within an aria-hidden=true element are unavailable to users of assistive technologies, like a screen reader.
ARIA input fields have accessible names
Generic names are announced to users of assistive technologies, like a screen reader, when an input field does not have an accessible name specified.
ARIA `meter` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
ARIA `progressbar` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
`[role]`s have all required `[aria-*]` attributes
Some ARIA roles have required 'aria-*' attributes, which provide essential information about state and functionality.
`[role]` values are valid
All ARIA roles require valid values to perform their intended functions.
ARIA toggle fields have accessible names
Generic names are announced to users of assistive technologies, like a screen reader, when a toggle field does not have an accessible name specified.
ARIA `tooltip` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
ARIA `treeitem` elements have accessible names
Without accessible names on elements, screen readers will default to announcing a generic name, which means your content will be less accessible to users who rely on screen readers.
`[aria-*]` attributes are valid and not misspelled
ARIA attributes cannot be interpreted with invalid names when used by screen readers and other assistive technologies.

Names and labels

Buttons have an accessible name
Buttons become unusable as they are announced simply as "button" when the button does not have an accessible name, when used by screen readers and other assistive technologies.
Document has a `<title>` element
Search engines, screen reader users and other assistive technology users rely on the title to provide an overview of the page and to help determine if the page is relevant to their search.
No form fields have multiple labels
Having multiple labels for form fields can be confusing to assistive technologies, like a screen reader.
`<frame>` or `<iframe>` elements have a title
Screen reader users and other assistive technology users rely on frame titles to describe the contents of frames.
Image elements have `[alt]` attributes
Provide short and descriptive alternative text where possible on informative elements.
`<input type="image">` elements have `[alt]` text
Input buttons with alternative text assist screen readers and other assistive technology users to understand its purpose.
Form elements have associated labels
Screen readers and other assistive technologies rely on labels to properly announce form controls.
Links have a discernible name
In order to improve the navigation for screen reader and other assistive technology users, use link text that is unique, focusable and discernible.
`<object>` elements have `[alt]` text
It is advised that alt text is used on '<object>' elements in order to provide meaning to screen reader and other assistive technology users, as these technologies are unable to translate non-text content.

Contrast

Background and foreground colors have a sufficient contrast ratio
Many (if not most) users find low-contrast text difficult or impossible to read.

Tables and lists

`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
Screen readers and other assistive technologies may produce poor and inaccurate output when definition lists are not properly marked up.
Definition list items are wrapped in `<dl>` elements
In order for screen readers and other assistive technologies to properly announce definition list items ('<dt>' and '<dd>'), they must be wrapped in parent a '<dl>' element.
Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
Use proper list structure to aid screen readers and other assistive technologies.
List items (`<li>`) are contained within `<ul>` or `<ol>` parent elements
In order for screen readers to announce list items, ensure that list items ('<li>') are contained within parent '<ul>' or '<ol>' tags.
Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
Screen readers and other assistive technologies have features to make navigating tables easier. Ensure that '<td>' cells using the headers attribute only refer to other cells in the same table, to improve screen reader user experience.
`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
Screen readers and other assistive technologies have features to make navigating tables easier. Ensure that table headers refer to some set of cells, to improve screen reader user experience.

Internationalization and localization

`<html>` element has a `[lang]` attribute
It is advised to provide a lang attribute so that screen readers and other assistive technologies are guaranteed to announce the page's text correctly. When not provided, the user's default language setting will be used which may cause inaccuracies.
`<html>` element has a valid value for its `[lang]` attribute
Specify a valid BCP 47 language in order to help screen readers and other assistive technologies announce text properly.
`[lang]` attributes have a valid value
Specify a valid BCP 47 language on elements in order to help screen readers and other assistive technologies announce text properly.

Best practices

The document does not use `<meta http-equiv="refresh">`
Pages that refresh automatically cause a poor user experience as focus is directed back to the top of the page unexpectedly.
`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
For users with low vision who rely on screen magnification, ensure that zooming is not disabled.

Audio and video

`<video>` elements contain a `<track>` element with `[kind="captions"]`
Imperial.ac.uk may provide assistance to deaf or hearing-impaired users with captions on videos.

ARIA

Elements with an ARIA `[role]` that require children to contain a specific `[role]` are missing some or all of those required children.
Some ARIA parent roles cannot perform their intended functions if specific child roles are not used.
Failing Elements
`[role]`s are not contained by their required parent element
Some ARIA child roles cannot perform their intended functions if specific parent roles are not used.
Failing Elements
`[aria-*]` attributes do not have valid values
ARIA attributes cannot be interpreted with invalid values when used by screen readers and other assistive technologies.
Failing Elements
ARIA IDs are not unique
Ensure all ARIA ID values are unique to prevent elements from being overlooked by assistive technologies, like a screen reader.
Failing Elements

Manual Checks

The page has a logical tab order
The visual layout should be logical in its tab order and users cannot focus elements that are offscreen.
Interactive controls are keyboard focusable
Ensure that custom interactive controls are keyboard focusable and that a focus indicator is displayed.
Interactive elements indicate their purpose and state
Ensure that interactive elements (such as links and buttons) are distinguishable from non-interactive elements and that they indicate their state.
The user's focus is directed to new content added to the page
When new content (such as a dialogue) is added to the page, the user's focus should be directed to it.
User focus is not accidentally trapped in a region
Avoid focus being accidentally trapped when a user tabs in and out of controls or regions on page.
Custom controls have associated labels
Ensure that custom interactive controls have associated labels, which are provided by aria-label and aria-labelledby attributes.
Custom controls have ARIA roles
Ensure that all custom interactive controls have appropriate ARIA roles.
Visual order on the page follows DOM order
Ensure that the DOM order matches with the page's visual order, in order to improve navigation for screen readers and other assistive technologies.
Offscreen content is hidden from assistive technology
Ensure that offscreen content is hidden through the use of "display:none" styling or the aria-hidden attribute.
HTML5 landmark elements are used to improve navigation
Elements such as <main> and <nav> are recommended as they are used by screen readers and other assistive technologies to improve keyboard navigation.
73

Best Practices

Indicates the recommended, best practices currently in place on the page and highlights the best practices that imperial.ac.uk should incorporate. This includes practices such as protecting pages with HTTPS.

Audits

Avoids requesting the geolocation permission on page load
When requesting a user's location, provide context or consider tying the request to a user action to avoid confusion and mistrust from users.
Avoids requesting the notification permission on page load
When requesting permission to send notifications, provide context or consider tying the request to a user action to avoid confusion and mistrust from users.
Avoids front-end JavaScript libraries with known security vulnerabilities
Ensure that the use of third-party scripts is minimal and that only trusted third-party scripts are used as some may contain known security vulnerabilities which may be exploited by attackers.

Audits

Allows users to paste into password fields
Ensure that password inputs may be pasted into to aid in the user's ability to use password managers and improve security.
Displays images with correct aspect ratio
Ensure that image display dimensions match their natural aspect ratio.
Serves images with appropriate resolution
For maximum image clarity, ensure images have natural dimensions and are proportional to the display size and pixel ratio.
Fonts with `font-display: optional` are preloaded
It is recommended that optional fonts are preloaded.

Audits

Page has the HTML doctype
Ensure a doctype is specified to prevent the browser from switching to quirks-mode.
Properly defines charset
It is advised to declare a character encoding, optionally via a <meta> tag in the first 1024 bytes of the HTML or in the Content-Type HTTP response header.

Audits

Avoids Application Cache
Application cache is deprecated and is no longer recommended.
Detected JavaScript libraries
Below is a list of all front-end JavaScript libraries that were detected on the page.
Name Version
jQuery
3.5.1
Modernizr
3.8.0
FlexSlider
core-js
core-js-pure@3.0.0
Avoids deprecated APIs
Avoid deprecated APIs which will eventually be removed the browser.
Page has valid source maps
Consider deploying source maps for added benefits such as the ability to debug while in production.
URL Map URL
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
http://www.imperial.ac.uk/assets/website/js/build/application.min.js.map
https://browser.sentry-cdn.com/5.29.0/bundle.min.js
https://browser.sentry-cdn.com/5.29.0/bundle.min.js.map
No issues in the `Issues` panel in Chrome Devtools
There may be unresolved issues logged to Chrome Devtools.

Audits

Does not use HTTPS — 48 insecure requests found
Ensure that all pages are protected with HTTPS (including those that do not handle sensitive data) as HTTPS prevents tampering and passive listening on communications between the app and its users. Additionally, HTTPS is a prerequisite for HTTP/2 and many new web platform APIs.
Insecure URL Request Resolution
http://imperial.ac.uk/
Allowed
http://www.imperial.ac.uk/
Allowed
http://www.imperial.ac.uk/assets/website/fonts/icons/fonts/imperial-icons.woff?vrmf2d
Allowed
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Regular.woff2
Allowed
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Bold.woff2
Allowed
http://www.imperial.ac.uk/assets/website/stylesheets/css/screen.1.24.10.css
Allowed
http://www.imperial.ac.uk/assets/website/stylesheets/css/color-themes.1.24.10.css
Allowed
http://www.imperial.ac.uk/assets/website/js/lib/jquery3.min.js
Allowed
http://www.imperial.ac.uk/assets/website/js/build/application.1.24.10.min.js
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616534487742_collegeheader2017_x2.webp
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616514117115_collegeheader2017_x2.webp
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage_1616499842491_collegeheader2017_x2.webp
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/City_of_London_65396749--tojpeg_1417615028107_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/ICL_Graduation_406--t_1417616392639_x2--tojpeg_1549642146125_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/imp_130820_campus1_lib_008--tojpeg_1417607683035_x2--tojpeg_1417682075073_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Impact--tojpeg_1417606493780_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/News--tojpeg_1417606851616_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/181101_natwilai_pae_drone_entrepreneur_031-%281%29--t_1542107706895_x1--tojpeg_1557236663888_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/15-02-ImperialPodcast_banner_4--tojpeg_1431608741948_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/IT-survey1--tojpeg_1525171251932_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Student-blogs--tojpeg_1514904013265_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Lion--tojpeg_1554882885019_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/campus--tojpeg_1416836905639_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Mega-menu-White-City-Campus-image--tojpeg_1493969367737_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/18-10-Imperial-Today-and-Podcast-promotion-generic_homepage2--tojpeg_1541498866946_x05.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/newseventsimage-1616515729089-mainnews2012-x1_1616577243441_x2.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/europe-at-night-from-space-nasa-tojpeg-1552495425942-x1_1607945350182_x2.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/21-03-covid-updates-homepage-button-v2-3_1616427399470_x4.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/lcp_1611683980352_eventpanel2018_x2.webp
Allowed
http://www.imperial.ac.uk/assets/website/images/placeholder/events/events-placeholder_4_eventpanel2018_x2.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/Alumni--tojpeg_1464879550264_x1.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/180510_mitchell_wayne_laboratory_skills_002--tojpeg_1583940077847_x05.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/0000_191111_autumn_library_queens_lawn_001--tojpeg_1583940105577_x05.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/190110_ambassadors_tower_bridge_001--tojpeg_1583940003078_x05.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/7Q8A6288--tojpeg_1583940852404_x05.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/strategy--tojpeg_1584468761509_x2.jpg
Allowed
http://www.imperial.ac.uk/assets/website/stylesheets/css/print.1.24.10.css
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/services-for-partners--tojpeg_1584469110993_x2.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/research-impact--tojpeg_1584469039182_x2.jpg
Allowed
http://www.imperial.ac.uk/ImageCropToolT4/imageTool/uploaded-images/support-for-staff--tojpeg_1584469207028_x2.jpg
Allowed
http://www.googletagmanager.com/gtm.js?id=GTM-PS52
Allowed
http://www.imperial.ac.uk/assets/website/images/common/hatch-grey.png
Allowed
http://www.imperial.ac.uk/assets/website/images/sprite_double/logo-footer.png
Allowed
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Medium.woff2
Allowed
http://www.imperial.ac.uk/assets/website/fonts/fira-sans/FiraSans-Italic.woff2
Allowed
http://www.googletagmanager.com/gtag/js?id=G-LME5ZDDFS0&l=dataLayer&cx=c
Allowed
http://www.google-analytics.com/analytics.js
Allowed
http://9752811.fls.doubleclick.net/activityi;src=9752811;type=phdsc20;cat=allpgrt;ord=1;num=328558929480;gtm=2wg3h0;auiddc=1600686856.1616608844;~oref=http%3A%2F%2Fwww.imperial.ac.uk%2F?
Allowed

Audits

Registers an `unload` listener
The 'unload' event does not fire reliably, causing issues with browser optimizations such as the Back-Forward Cache. It is recommended that 'pagehide' or 'visibilitychange' events are used instead.
Source
Browser errors were logged to the console
Below is a list of all errors logged to the console, which indicate unresolved problems on the site.
Source Description
Failed to load resource: net::ERR_BLOCKED_BY_CLIENT.Inspector
Failed to load resource: net::ERR_BLOCKED_BY_CLIENT.Inspector
97

SEO

Indicates how well the page is optimized for ranking in search engines and highlights Search Engine Optimization (SEO) opportunities for imperial.ac.uk. This includes optimizations such as providing meta data.

Mobile Friendly

Has a `<meta name="viewport">` tag with `width` or `initial-scale`
It is advised to use a '<meta name="viewport">' tag for the optimization of imperial.ac.uk on mobile screens.
Document uses legible font sizes — 100% legible text
Font sizes of 12px or less are too small to most mobile users without user gestures and further action. Aim for more than 60% of page text to use font sizes greater than 12px.
Source Selector % of Page Text Font Size
100.00%
≥ 12px

Content Best Practices

Document has a `<title>` element
Search engines, screen reader users and other assistive technology users rely on the title to provide an overview of the page and to help determine if the page is relevant to their search.
Document has a meta description
Meta descriptions may be used by search engines when displaying a link to the page and should concisely summarize the page's content.
Links have descriptive text
Make use of descriptive link text to assist search engines in understanding the content.
Image elements have `[alt]` attributes
Provide short and descriptive alternative text where possible on informative elements.
Document has a valid `hreflang`
Search engines can be instructed to list specific versions of a page for a given language or region through the use of hreflang links.
Document has a valid `rel=canonical`
Search engines can be suggested which URL should be shown in search results through the use of canonical links.
Document avoids plugins
The content of plugins cannot be indexed by search engines and many devices either restrict or do not support them.

Crawling and Indexing

Page has successful HTTP status code
Avoid pages with unsuccessful HTTP status codes as they may not be indexed by search engines.
Links are crawlable
Ensure that the 'href' attribute of anchor elements links to the appropriate destination. This allows for more pages of the site to be discovered by search engines.
Page isn’t blocked from indexing
Pages that cannot be crawled by search engines cannot be indexed or included in their search results. Ensure that search engines have permission to crawl all pages that should be indexed.
robots.txt is valid
Malformed robots.txt files prevent crawlers from understanding how a site wants to be crawled or indexed, which can be devastating to SEO.

Manual Checks

Structured data is valid
Structured data can be validated through the use of the Structured Data Testing Tool and the Structured Data Linter.
33

Progressive Web App

Indicates how valid the aspects of a Progressive Web App (PWA) are for the page and highlights opportunities to enable/improve the PWA of imperial.ac.uk. This includes details about web app manifests.

PWA Optimized

Content is sized correctly for the viewport
Ensure that the width of the app's content matches the width of the viewport, otherwise the app might not be optimized for mobile screens.
Has a `<meta name="viewport">` tag with `width` or `initial-scale`
It is advised to use a '<meta name="viewport">' tag for the optimization of imperial.ac.uk on mobile screens.
Provides a valid `apple-touch-icon`
iOS users of Progressive Web Apps will benefit from an apple touch icon, which can be defined with 'apple-touch-icon', which must point to a non-transparent 192px (or 180px) square PNG.

Installable

Web app manifest or service worker do not meet the installability requirements — 1 reason
User engagement may be increased by leveraging the browsers ability to proactively prompt users to add the app to their homescreen.
Failure reason
No manifest was fetched

PWA Optimized

Does not register a service worker that controls page and `start_url`
A service worker is used to provide Progressive Web Apps the use of features such as working offline, the ability for the app to be added to the homescreen as well as push notifications.
Does not redirect HTTP traffic to HTTPS
It is advised to redirect all HTTP traffic to HTTPS, in order to enable secure web features for all users.
Is not configured for a custom splash screen
Themed splash screens ensure a high-quality user experience at launch for app users.
View Data
Does not set a theme color for the address bar.
A theme may be applied to the browser address bar, which ideally can be made to match the site.
View Data
Manifest doesn't have a maskable icon
Maskable icons are great to ensure that images fill the entire shape when installing the app on a device.

Manual Checks

Site works cross-browser
Ensure that the Progressive Web App works correctly across every major browser.
Page transitions don't feel like they block on the network
Users perceive apps with responsive, snappy transitions as higher peforming and ensures a great user experience, even on a slow network.
Each page has a URL
Ensure that all pages are deep linkable via URL. They should also be unique for the purpose of shareability on social media.
Hosting

Server Location

Server IP Address: 146.179.40.148
Continent: Europe
Country: United Kingdom
United Kingdom Flag
Region:
City:
Longitude: -0.1224
Latitude: 51.4964
Currencies: GBP
Languages: English

Web Hosting Provider

Registration

Domain Registrant

Private Registration: No
Name:
Organization:
Country:
City:
State:
Post Code:
Email:
Phone:
Note: Registration information is derived from various sources and may be inaccurate.

Domain Registrar

Security

Visitor Safety

Mature Content: Not Likely
McAfee WebAdvisor Rating: Unknown
WOT Rating: 4.8/5 (5 reviews)
WOT Trustworthiness: 95/100
WOT Child Safety: 94/100
Note: Safety information is not guaranteed.

SSL/TLS Certificate

Issued To: www.imperial.ac.uk
Issued By: QuoVadis Global SSL ICA G3
Valid From: 8th December, 2020
Valid To: 8th December, 2021
Subject: CN = www.imperial.ac.uk
O = Imperial College of Science, Technology and Medicine
L = London
S = GB
Hash: 9c0f9836
Issuer: CN = QuoVadis Global SSL ICA G3
O = QuoVadis Limited
S = BM
Version: 2
Serial Number: 0x155C86B582BFB5851A59A1D937473BEDA085B251
Serial Number (Hex): 155C86B582BFB5851A59A1D937473BEDA085B251
Valid From: 8th December, 2024
Valid To: 8th December, 2024
Signature Algorithm (Short Name): RSA-SHA256
Signature Algorithm (Long Name): sha256WithRSAEncryption
Authority Key Identifier: keyid:B3:12:89:B5:A9:4B:35:BC:15:00:F0:80:E9:D8:78:87:F1:13:7C:76
Extended Key Usage: TLS Web Client Authentication, TLS Web Server Authentication
CRL Distribution Points:
Full Name:
URI:http://crl.quovadisglobal.com/qvsslg3.crl

Certificate Policies: Policy: 1.3.6.1.4.1.8024.0.2.100.1.1
CPS: http://www.quovadisglobal.com/repository
Policy: 2.23.140.1.2.2

Authority Information Access: CA Issuers - URI:http://trust.quovadisglobal.com/qvsslg3.crt
OCSP - URI:http://ocsp.quovadisglobal.com

SCT List: Signed Certificate Timestamp:
Version : v1 (0x0)
Log ID : F6:5C:94:2F:D1:77:30:22:14:54:18:08:30:94:56:8E:
E3:4D:13:19:33:BF:DF:0C:2F:20:0B:CC:4E:F1:64:E3
Timestamp : Dec 8 18:04:01.938 2020 GMT
Extensions: none
Signature : ecdsa-with-SHA256
30:44:02:20:54:8C:38:2C:5D:64:FB:5A:1B:AF:57:62:
D3:09:56:19:B0:1C:B8:81:8A:44:A0:2E:3E:05:D7:55:
2F:5B:64:96:02:20:6E:58:9B:58:36:79:3F:80:19:5B:
4B:A1:25:89:35:0A:07:06:34:72:65:0A:F3:9F:BB:40:
A5:AB:B1:08:D1:EF
Signed Certificate Timestamp:
Version : v1 (0x0)
Log ID : 55:81:D4:C2:16:90:36:01:4A:EA:0B:9B:57:3C:53:F0:
C0:E4:38:78:70:25:08:17:2F:A3:AA:1D:07:13:D3:0C
Timestamp : Dec 8 18:04:02.009 2020 GMT
Extensions: none
Signature : ecdsa-with-SHA256
30:46:02:21:00:C6:D4:CC:A0:F2:41:D3:AF:79:B0:23:
D6:D7:8E:FF:6F:A1:5D:F3:78:49:F3:F2:7A:26:47:8F:
FC:4D:2A:74:C6:02:21:00:8A:6F:A3:2C:C3:7E:2F:56:
C7:F3:2A:61:D2:60:77:C7:3E:5F:F6:AC:22:B8:1B:CC:
79:44:DA:25:CB:AC:90:34
Key Usage: Digital Signature, Key Encipherment
Basic Constraints: CA:FALSE
Subject Alternative Name: DNS:ic.ac.uk
DNS:imperial.ac.uk
DNS:www.ic.ac.uk
DNS:www.imperial.ac.uk
Technical

DNS Lookup

A Records

Host IP Address Class TTL
imperial.ac.uk. 146.179.40.148 IN 21599

NS Records

Host Nameserver Class TTL
imperial.ac.uk. ns2.ic.ac.uk. IN 21599
imperial.ac.uk. auth0.dns.cam.ac.uk. IN 21599
imperial.ac.uk. ns1.ic.ac.uk. IN 21599
imperial.ac.uk. ns0.ic.ac.uk. IN 21599

AAAA Records

IP Address Class TTL
2001:630:12:600:1:2:0:172 IN 21599

MX Records

Priority Host Server Class TTL
10 imperial.ac.uk. mx3.cc.ic.ac.uk. IN 21599
10 imperial.ac.uk. mx2.cc.ic.ac.uk. IN 21599
10 imperial.ac.uk. mx1.cc.ic.ac.uk. IN 21599
10 imperial.ac.uk. mx4.cc.ic.ac.uk. IN 21599

SOA Records

Domain Name Primary NS Responsible Email TTL
imperial.ac.uk. ns0.imperial.ac.uk. hostmaster.imperial.ac.uk. 3599

TXT Records

Host Value Class TTL
imperial.ac.uk. jpTnP0a85DNKFLkx3olXeqgv6Fmksm7XhTp1ObH+mitHv34hgwMAH7sDmZsqdrYYrcftGIRG4gbhRzaQXhZe2Q== IN 599
imperial.ac.uk. B7OdSiuxOT4nDzVKc3rvRvPCmauZX0/VUm0gfNk4rF2in08TlPIw9PTxeO7uivisEBoFTWH/3lkOCnEH+lKdUw== IN 599
imperial.ac.uk. google-site-verification=MdcxxWVSgL9c9_78aEbXoFSAQTYjChLxqmZKcLcc7CI IN 599
imperial.ac.uk. QuoVadis=074d27b3-587e-4c96-b5be-881e3fa0d7b9 IN 599
imperial.ac.uk. 1a531ca6-e94c-49b4-873a-d9a369194f9d.100718 IN 599
imperial.ac.uk. v=spf1 IN 599

HTTP Response Headers

HTTP-Code: HTTP/1.1 200 OK
Cache-Control: private
Content-Type: text/html; charset=UTF-8
Server: Microsoft-IIS/10.0
Date: 24th March, 2021
Content-Length: 0
X-Web-Server: icwww3
Set-Cookie: *
X-Powered-By: ARR/3.0
X-ARR-Server: ICRP10
Content-Security-Policy: frame-ancestors 'self' *.imperial.ac.uk *.ic.ac.uk

Whois Lookup

Created: 31st July, 1996
Changed:
Expires:
Registrar: No registrar listed. This domain is directly registered with Nominet.
Status:
Nameservers: auth03.ns.uu.net
dns-3.dfn.de
ns0.ja.net
ns1.surfnet.nl
ns2.ja.net
ns3.ja.net
ns4.ja.net
Owner Organization: The JNT Association
Full Whois: Domain name:
ac.uk

Registrant:
The JNT Association

Registrant type:
Other

Registrant's address:
Lumen House
Library Avenue
Harwell
Didcot
OX11 OSG
GB

Registrar:
No registrar listed. This domain is directly registered with Nominet.

Relevant dates:
Registered on: before Aug-1996
Registration status:
No registration status listed.

Name servers:
ns0.ja.net.
ns2.ja.net.
ns3.ja.net.
ns4.ja.net.
auth03.ns.uu.net.
ns1.surfnet.nl.
dns-3.dfn.de.


WHOIS lookup made at 18:00:05 24-Mar-2021

--
This WHOIS information is provided for free by Nominet UK the central registry
for .uk domain names. This information and the .uk WHOIS are:

Copyright Nominet UK 1996 - 2021.

You may not access the .uk WHOIS or use any data from it except as permitted
by the terms of use available in full at https://www.nominet.uk/whoisterms,
which includes restrictions on: (A) use of the data for advertising, or its
repackaging, recompilation, redistribution or reuse (B) obscuring, removing
or hiding any or all of this notice and (C) exceeding query rate or volume
limits. The data is provided on an 'as-is' basis and may lag behind the
register. Access may be withdrawn or restricted at any time.

Nameservers

Name IP Address
auth03.ns.uu.net 198.6.1.83
dns-3.dfn.de 193.174.75.58
ns0.ja.net 193.63.94.20
ns1.surfnet.nl 192.87.106.101
ns2.ja.net 193.63.105.17
ns3.ja.net 193.63.106.103
ns4.ja.net 193.62.157.66
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Domain Subdomain
www3

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