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Lighthouse Mobile

· 0 checks — Mobile Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.
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Detailed Report

Audit breakdown by category with detailed findings.

46

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Performance issues directly impact user engagement and conversion rates.

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

RequestCache TTLTransfer Size
www.reading.ac.uk/homepage/web/multimediafiles/ug-open-days-banner.jpg0.0 ms404.4 KiB
/homepage/web/multimediafiles/B35381-Spring-Webinar-Graph...0.0 ms233.1 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/assets-css-main.css0.0 ms198.7 KiB
www.reading.ac.uk/homepage/web/multimediafiles/sunrise-from-space.jpg0.0 ms197.2 KiB
/homepage/web/multimediafiles/2026-centenary-merchandise-...0.0 ms184.8 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js0.0 ms176.7 KiB
/homepage/web/multimediafiles/2026-centenary-merchandise-...0.0 ms170.2 KiB
www.reading.ac.uk/homepage/web/multimediafiles/centenary-homepage-banner.jpg0.0 ms126.1 KiB
www.reading.ac.uk/homepage/web/multimediafiles/assets-img-icons-s35e128c89f.png0.0 ms99.7 KiB
app.termly.io/resource-blocker/b846a047-fc56-4159-aaf3-7bdc36e9790714400.0 s143.4 KiB
/homepage/web/multimediafiles/assets-new-images-landing_f...0.0 ms92.9 KiB
www.reading.ac.uk/homepage/web/multimediafiles/connectedworld296x150.jpg0.0 ms92.1 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/js-jquery-2.1.1.js0.0 ms82.7 KiB
/homepage/web/multimediafiles/assets-home-Great-course-se...0.0 ms75.6 KiB
/homepage/web/multimediafiles/assets-home-Explore-student...0.0 ms53.7 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/css-main.css0.0 ms53.1 KiB
/homepage/web/multimediafiles/assets-home-Get-a-Room1-296...0.0 ms48.3 KiB
www.reading.ac.uk/homepage/web/multimediafiles/teaching-and-learning-296x150.jpg0.0 ms42.8 KiB
/homepage/web/multimediafiles/assets-home-latest-news-296...0.0 ms40.4 KiB
www.reading.ac.uk/homepage/web/multimediafiles/business-296x150px.jpg0.0 ms40.2 KiB
www.reading.ac.uk/homepage/web/files/campaigns/effra-regular.woff0.0 ms30.3 KiB
www.reading.ac.uk/homepage/web/files/campaigns/effra-bold.woff0.0 ms29.6 KiB
www.reading.ac.uk/homepage/web/files/campaigns/effra-light.woff0.0 ms29.6 KiB
www.reading.ac.uk/homepage/web/files/campaigns/effra-heavy.woff0.0 ms28.9 KiB
www.reading.ac.uk/homepage/web/files/campaigns/effra-medium.woff0.0 ms28.8 KiB
www.reading.ac.uk/homepage/web/files/campaigns/rdgvesta-regular.woff0.0 ms28.7 KiB
www.reading.ac.uk/homepage/web/multimediafiles/unibuddy256x150.jpg0.0 ms26.2 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/web-components.min.js0.0 ms18.3 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/css-hero-slider-style-2.css0.0 ms18.0 KiB
www.reading.ac.uk/homepage/web/multimediafiles/assets-home-uorm-1-296x150.jpg0.0 ms16.1 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/js-modernizr.custom.04512.js0.0 ms15.6 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/february-assets-css-main.css0.0 ms12.7 KiB
www.reading.ac.uk/homepage/web/multimediafiles/legacy-uor-home-mobile.png0.0 ms6.1 KiB
app.termly.io/resource-blocker/support/894-6156b36a131577c56e7e.min.js14400.0 s8.4 KiB
www.reading.ac.uk/sc93/js/uor.module.cookie-blocker.js0.0 ms5.4 KiB
www.reading.ac.uk/homepage/web/multimediafiles/legacy-uor-home.png0.0 ms5.4 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/js-slider2.js0.0 ms4.7 KiB
www.reading.ac.uk/homepage/web/multimediafiles/weibo.png0.0 ms4.1 KiB
/homepage/web/multimediafiles/assets-new-ig-investments-w...0.0 ms4.0 KiB
www.reading.ac.uk/homepage/web/multimediafiles/assets-new-ig-book-white.gif0.0 ms3.8 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/clearing-2025.css0.0 ms2.0 KiB
app.termly.io/resource-blocker/support/524-7d36cb122791702e3df2.min.js14400.0 s2.7 KiB
www.reading.ac.uk/homepage/web/multimediafiles/assets-new-ig-chart-94-white.gif0.0 ms1.7 KiB
app.termly.io/resource-blocker/support/861-8c5cb8c2beda05e3176b.min.js14400.0 s2.3 KiB
www.reading.ac.uk/homepage/web/multimediafiles/legacy-hamburger.png0.0 ms1.5 KiB
www.reading.ac.uk/homepage/web/multimediafiles/magnifying-glass.svg0.0 ms1.1 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/js-main.min.js0.0 ms962 B
www.reading.ac.uk/homepage/web/files/dr-homepage/legacy-print.css0.0 ms938 B
app.termly.io/resource-blocker/support/377-e518d8a5c599aa1c5977.min.js14400.0 s873 B

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLEst Savings
www.reading.ac.uk/homepage/web/files/campaigns/effra-bold.woff35 ms
www.reading.ac.uk/homepage/web/files/campaigns/effra-regular.woff35 ms
www.reading.ac.uk/homepage/web/files/campaigns/rdgvesta-regular.woff35 ms
www.reading.ac.uk/homepage/web/files/campaigns/effra-light.woff30 ms
www.reading.ac.uk/homepage/web/files/campaigns/effra-heavy.woff30 ms
www.reading.ac.uk/homepage/web/files/campaigns/effra-medium.woff30 ms

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:source label:Top function call valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:37.409 source:map[column:9731 line:1 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]]]
headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:26.104 source:map[column:21566 line:0 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:0.267 source:map[column:21663 line:0 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:0.141 source:map[column:21893 line:0 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:0.106 source:map[column:22316 line:0 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:0.182 source:map[column:22475 line:0 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:0.142 source:map[column:22620 line:0 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:2.489 source:map[column:11016 line:2 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:3.038 source:map[column:3408 line:0 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:1.678 source:map[column:12109 line:2 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:2.006 source:map[column:10339 line:2 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]] map[reflowTime:1.256 source:map[column:13537 line:6 type:source-location url:https://www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js urlProvider:network]]]

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
ul.cd-hero-slider > li.selected > div.cd-img-container > img.mobile ul.cd-hero-slider > li.selected > div.cd-img-container > img.mobile
www.reading.ac.uk/homepage/web/multimediafiles/centenary-homepage-banner.jpg125.7 KiB115.4 KiB
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/connectedworld296x150.jpg91.7 KiB84.5 KiB
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
/homepage/web/multimediafiles/assets-home-Great-course-se...75.2 KiB68.0 KiB
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
/homepage/web/multimediafiles/assets-home-Explore-student...53.3 KiB46.1 KiB
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
/homepage/web/multimediafiles/assets-home-Get-a-Room1-296...47.9 KiB40.6 KiB
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/teaching-and-learning-296x150.jpg42.4 KiB35.2 KiB
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
/homepage/web/multimediafiles/assets-home-latest-news-296...40.0 KiB32.8 KiB
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/business-296x150px.jpg39.8 KiB32.5 KiB
div.cta-content > a.icon-map > i.cta-icon > ::before div.cta-content > a.icon-map > i.cta-icon > ::before
www.reading.ac.uk/homepage/web/multimediafiles/assets-img-icons-s35e128c89f.png99.3 KiB20.2 KiB
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/unibuddy256x150.jpg25.8 KiB18.6 KiB
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/assets-home-uorm-1-296x150.jpg15.7 KiB8.4 KiB
University of Reading div.mega-btn > div.mobile-home > a > img
www.reading.ac.uk/homepage/web/multimediafiles/legacy-uor-home-mobile.png5.7 KiB5.3 KiB

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-0-IMG
nodeLabel: ul.cd-hero-slider > li.selected > div.cd-img-container > img.mobile
path: 6,HTML,2,BODY,10,DIV,0,DIV,4,DIV,0,DIV,0,SECTION,0,UL,8,LI,0,DIV,1,IMG
selector: ul.cd-hero-slider > li.selected > div.cd-img-container > img.mobile
snippet: <img class="mobile" src="..\homepage\web\multimediafiles\centenary-homepage-banner.jpg" alt="">

HTTP/2 and HTTP/3 offer many benefits over HTTP/1.1, such as multiplexing. Learn more about using modern HTTP.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLProtocol
www.reading.ac.uk/http/1.1
www.reading.ac.uk/sc93/js/uor.module.cookie-blocker.jshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/assets-css-main.csshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/february-assets-css-main.csshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/css-main.csshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/css-hero-slider-style-2.csshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/clearing-2025.csshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/js-modernizr.custom.04512.jshttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/legacy-hamburger.pnghttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/legacy-uor-home-mobile.pnghttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/legacy-uor-home.pnghttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/centenary-homepage-banner.jpghttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/ug-open-days-banner.jpghttp/1.1
/homepage/web/multimediafiles/B35381-Spring-Webinar-Graph...http/1.1
www.reading.ac.uk/homepage/web/multimediafiles/sunrise-from-space.jpghttp/1.1
/homepage/web/multimediafiles/2026-centenary-merchandise-...http/1.1
/homepage/web/multimediafiles/2026-centenary-merchandise-...http/1.1
/homepage/web/multimediafiles/assets-home-Great-course-se...http/1.1
/homepage/web/multimediafiles/assets-home-Explore-student...http/1.1
www.reading.ac.uk/homepage/web/multimediafiles/unibuddy256x150.jpghttp/1.1
/homepage/web/multimediafiles/assets-home-latest-news-296...http/1.1
www.reading.ac.uk/homepage/web/multimediafiles/teaching-and-learning-296x150.jpghttp/1.1
/homepage/web/multimediafiles/assets-home-Get-a-Room1-296...http/1.1
www.reading.ac.uk/homepage/web/multimediafiles/connectedworld296x150.jpghttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/business-296x150px.jpghttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/assets-home-uorm-1-296x150.jpghttp/1.1
/homepage/web/multimediafiles/assets-new-images-landing_f...http/1.1
www.reading.ac.uk/homepage/web/multimediafiles/weibo.pnghttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/js-jquery-2.1.1.jshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/js-main.min.jshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/js-slider2.jshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.jshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/web-components.min.jshttp/1.1
www.reading.ac.uk/homepage/web/files/dr-homepage/legacy-print.csshttp/1.1
www.reading.ac.uk/homepage/web/files/campaigns/effra-light.woffhttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/assets-img-icons-s35e128c89f.pnghttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/magnifying-glass.svghttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/assets-new-ig-chart-94-white.gifhttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/assets-new-ig-book-white.gifhttp/1.1
/homepage/web/multimediafiles/assets-new-ig-investments-w...http/1.1
www.reading.ac.uk/homepage/web/files/campaigns/effra-heavy.woffhttp/1.1
www.reading.ac.uk/homepage/web/files/campaigns/effra-medium.woffhttp/1.1
www.reading.ac.uk/homepage/web/files/campaigns/effra-bold.woffhttp/1.1
www.reading.ac.uk/homepage/web/files/campaigns/effra-regular.woffhttp/1.1
www.reading.ac.uk/homepage/web/files/campaigns/rdgvesta-regular.woffhttp/1.1
www.reading.ac.uk/search/404.htmhttp/1.1
www.reading.ac.uk/homepage/web/multimediafiles/legacy-favicon.icohttp/1.1

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.
title: Preconnected origins
description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.
title: Preconnect candidates
value: No additional origins are good candidates for preconnecting

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer SizeDuration
www.reading.ac.uk/homepage/web/files/dr-homepage/assets-css-main.css198.7 KiB2.9 s
www.reading.ac.uk/homepage/web/files/dr-homepage/css-main.css53.1 KiB1.7 s
www.reading.ac.uk/homepage/web/files/dr-homepage/js-modernizr.custom.04512.js15.6 KiB928 ms
www.reading.ac.uk/sc93/js/uor.module.cookie-blocker.js5.4 KiB621 ms
www.reading.ac.uk/homepage/web/files/dr-homepage/february-assets-css-main.css12.7 KiB774 ms
www.reading.ac.uk/homepage/web/files/dr-homepage/css-hero-slider-style-2.css18.0 KiB1.1 s
www.reading.ac.uk/homepage/web/files/dr-homepage/clearing-2025.css2.0 KiB467 ms

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 1.4 s
URLTime Spent
reading.ac.uk/768 ms
www.reading.ac.uk/630 ms
www.reading.ac.uk/0.0 ms

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Diagnostics

Minifying CSS files can reduce network payload sizes. Learn how to minify CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 170 ms 36.3 KiB
URLTransfer SizeEst Savings
www.reading.ac.uk/homepage/web/files/dr-homepage/assets-css-main.css198.7 KiB14.6 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/css-main.css53.1 KiB12.6 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/css-hero-slider-style-2.css18.0 KiB6.3 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/february-assets-css-main.css12.7 KiB2.8 KiB

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 900 ms 227.8 KiB
URLTransfer SizeEst Savings
www.reading.ac.uk/homepage/web/files/dr-homepage/assets-css-main.css198.3 KiB167.7 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/css-main.css52.7 KiB36.6 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/css-hero-slider-style-2.css17.6 KiB12.5 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/february-assets-css-main.css12.3 KiB11.1 KiB

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 2.9 s 621.1 KiB
URLTransfer SizeEst Savings
www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js176.3 KiB102.3 KiB
www.googletagmanager.com/gtag/js?id=AW-11016496176&cx=c&gtm=4e64k0143.5 KiB87.4 KiB
www.googletagmanager.com/gtag/js?id=DC-13730620&cx=c&gtm=4e64k0131.7 KiB80.8 KiB
www.googletagmanager.com/gtag/js?id=DC-13024755&cx=c&gtm=4e64k0129.2 KiB80.5 KiB
www.googletagmanager.com/gtag/js?id=DC-8556031&cx=c&gtm=4e64k0129.2 KiB80.5 KiB
www.googletagmanager.com/gtm.js?id=GTM-TC325M192.1 KiB79.5 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/js-jquery-2.1.1.js82.3 KiB55.7 KiB
app.termly.io/resource-blocker/b846a047-fc56-4159-aaf3-7bdc36e97907143.2 KiB54.4 KiB

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Script Evaluation1.1 s
Other386 ms
Style & Layout303 ms
Script Parsing & Compilation271 ms
Parse HTML & CSS48 ms
Rendering31 ms
Garbage Collection26 ms

Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 2.3 KiB
URLTransfer SizeEst Savings
www.reading.ac.uk/sc93/js/uor.module.cookie-blocker.js4.6 KiB2.3 KiB

Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer Size
www.reading.ac.uk/homepage/web/multimediafiles/ug-open-days-banner.jpg404.4 KiB
/homepage/web/multimediafiles/B35381-Spring-Webinar-Graph...233.1 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/assets-css-main.css198.7 KiB
www.reading.ac.uk/homepage/web/multimediafiles/sunrise-from-space.jpg197.2 KiB
www.googletagmanager.com/gtm.js?id=GTM-TC325M192.5 KiB
/homepage/web/multimediafiles/2026-centenary-merchandise-...184.8 KiB
www.reading.ac.uk/homepage/web/files/dr-homepage/web-library.min.js176.7 KiB
/homepage/web/multimediafiles/2026-centenary-merchandise-...170.2 KiB
www.googletagmanager.com/gtag/js?id=AW-11016496176&cx=c&gtm=4e64k0143.5 KiB
app.termly.io/resource-blocker/b846a047-fc56-4159-aaf3-7bdc36e97907143.4 KiB

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
/homepage/web/multimediafiles/assets-home-Great-course-se...
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
/homepage/web/multimediafiles/assets-home-Explore-student...
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/unibuddy256x150.jpg
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
/homepage/web/multimediafiles/assets-home-latest-news-296...
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/teaching-and-learning-296x150.jpg
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
/homepage/web/multimediafiles/assets-home-Get-a-Room1-296...
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/connectedworld296x150.jpg
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/business-296x150px.jpg
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
www.reading.ac.uk/homepage/web/multimediafiles/assets-home-uorm-1-296x150.jpg
weibo icon div.pane > div.component > a.icon > img
www.reading.ac.uk/homepage/web/multimediafiles/weibo.png

More information about the performance of your application. These numbers don't directly affect the Performance score.

●Layout shift culprits
●Optimize DOM size
●LCP breakdown
●Optimize viewport for mobile
●JavaScript execution time 1.3 s
●Avoid long main-thread tasks 12 long tasks found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 30 ms
●Server Backend Latencies 90 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 60 ms
○INP breakdown
○User Timing marks and measures
○Avoid non-composited animations
○Avoid large layout shifts
93

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

ARIA

ARIA dialog elements without accessible names may prevent screen readers users from discerning the purpose of these elements. Learn how to make ARIA dialog elements more accessible.

Why this matters

Informational: a Permissions-Policy directive showing feature -> allowed origins.

Source: MDN Permissions-Policy

Failing Elements
We use essential cookies to make our site work. With your consent, we may also … div#termly-code-snippet-support > div > div.termly-styles-root-f9c495 > div.termly-styles-consent-banner-fa199d

These are opportunities to improve the usage of ARIA in your application which may enhance the experience for users of assistive technology, like a screen reader.

Contrast

Low-contrast text is difficult or impossible for many users to read. Learn how to provide sufficient color contrast.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
#1 nav > ul > li > a
#2 nav > ul > li > a
#3 nav > ul > li > a
#4 nav > ul > li > a
BACK TO TOP div.wrapper > div.wrapper-footer > div.mobile-back-to-top > a

These are opportunities to improve the legibility of your content.

○Interactive controls are keyboard focusable
○Interactive elements indicate their purpose and state
○The page has a logical tab order
○Visual order on the page follows DOM order
○User focus is not accidentally trapped in a region
○The user's focus is directed to new content added to the page
○HTML5 landmark elements are used to improve navigation
○Offscreen content is hidden from assistive technology
○Custom controls have associated labels
○Custom controls have ARIA roles
●`[aria-*]` attributes match their roles
●`[aria-hidden="true"]` is not present on the document `<body>`
●`[role]`s have all required `[aria-*]` attributes
●`[role]` values are valid
●`[aria-*]` attributes have valid values
●`[aria-*]` attributes are valid and not misspelled
●Buttons have an accessible name
●Image elements have `[alt]` attributes
●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
●`button`, `link`, and `menuitem` elements have accessible names
●ARIA attributes are used as specified for the element's role
●Elements use only permitted ARIA attributes
●Document has a `<title>` element
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●Links have a discernible name
●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
●No element has a `[tabindex]` value greater than 0
●Touch targets have sufficient size and spacing.
●Heading elements appear in a sequentially-descending order
●Skip links are focusable.
●Document has a main landmark.
●Deprecated ARIA roles were not used
○`[accesskey]` values are unique
○`[aria-hidden="true"]` elements do not contain focusable descendents
○ARIA input fields have accessible names
○ARIA `meter` elements have accessible names
○ARIA `progressbar` elements have accessible names
○Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
○`[role]`s are contained by their required parent element
○Elements with the `role=text` attribute do not have focusable descendents.
○ARIA toggle fields have accessible names
○ARIA `tooltip` elements have accessible names
○ARIA `treeitem` elements have accessible names
○The page contains a heading, skip link, or landmark region
○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
○Definition list items are wrapped in `<dl>` elements
○ARIA IDs are unique
○No form fields have multiple labels
○`<frame>` or `<iframe>` elements have a title
○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
○Input buttons have discernible text.
○`<input type="image">` elements have `[alt]` text
○Form elements have associated labels
○Links are distinguishable without relying on color.
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
○`[lang]` attributes have a valid value
○`<video>` elements contain a `<track>` element with `[kind="captions"]`
○Tables have different content in the summary attribute and `<caption>`.
○All heading elements contain content.
○Uses ARIA roles only on compatible elements
○Image elements do not have `[alt]` attributes that are redundant text.
○Identical links have the same purpose.
○Elements with visible text labels have matching accessible names.
○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
○`<td>` elements in a large `<table>` have one or more table headers.
69

Best Practices

Trust and Safety

All sites should be protected with HTTPS, even ones that don't handle sensitive data. This includes avoiding mixed content, where some resources are loaded over HTTP despite the initial request being served over HTTPS. HTTPS prevents intruders from tampering with or passively listening in on the communications between your app and your users, and is a prerequisite for HTTP/2 and many new web platform APIs. Learn more about HTTPS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Insecure URLRequest Resolution
www.reading.ac.uk/Allowed

User Experience

Image natural dimensions should be proportional to the display size and the pixel ratio to maximize image clarity. Learn how to provide responsive images.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLDisplayed sizeActual sizeExpected size
div.row > div.pane > div.image-placeholder > img div.row > div.pane > div.image-placeholder > img
/homepage/web/multimediafiles/assets-home-Great-course-se...399 x 202296 x 150599 x 303

Browser Compatibility

A character encoding declaration is required. It can be done with a `<meta>` tag in the first 1024 bytes of the HTML or in the Content-Type HTTP response header. Learn more about declaring the character encoding.

Why this matters

Performance issues directly impact user engagement and conversion rates.

General

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Why this matters

Performance issues directly impact user engagement and conversion rates.

SourceDescription
www.reading.ac.uk/search/404.htm
Failed to load resource: the server responded with a status of 404 (Page not found)
●Avoids deprecated APIs
●Avoids third-party cookies
●Allows users to paste into input fields
●Avoids requesting the geolocation permission on page load
●Avoids requesting the notification permission on page load
●Displays images with correct aspect ratio
●Page has the HTML doctype
●No issues in the `Issues` panel in Chrome Devtools
●Ensure CSP is effective against XSS attacks
●Use a strong HSTS policy
●Ensure proper origin isolation with COOP
●Mitigate DOM-based XSS with Trusted Types
●Detected JavaScript libraries
●Page has valid source maps
○Redirects HTTP traffic to HTTPS
○Mitigate clickjacking with XFO or CSP
92

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Crawling and Indexing

If your robots.txt file is malformed, crawlers may not be able to understand how you want your website to be crawled or indexed. Learn more about robots.txt.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Line #ContentError
18Disallow: http://www.rdg.ac.uk/WebStatsPattern should either be empty, start with "/" or "*"
19Disallow: http://www.reading.ac.uk/WebStatsPattern should either be empty, start with "/" or "*"

To appear in search results, crawlers need access to your app.

○Structured data is valid
●Page isn’t blocked from indexing
●Document has a `<title>` element
●Document has a meta description
●Page has successful HTTP status code
●Links have descriptive text
●Links are crawlable
●Image elements have `[alt]` attributes
●Document has a valid `hreflang`
○Document has a valid `rel=canonical`

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