Lighthouse Mobile

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

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Detailed Report

Audit breakdown by category with detailed findings.

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.

Request	Cache TTL	Transfer Size
video.ruhr-uni-bochum.de/cache/a7d5529448690fcbdbfcf58a22ad1622.webp	0.0 ms	111.0 KiB
statistic.ruhr-uni-bochum.de/matomo.js	0.0 ms	45.4 KiB

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]

items: [map[node:map[type:text value:Total] score:0.134347] map[node:map[boundingRect:map[bottom:8489 height:7922 left:0 right:412 top:567 width:412] lhId:page-2-DIV nodeLabel:Built to change Gebaut, um zu verändern: Seit 60 Jahren treibt die Ruhr-Univer… path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,1,DIV selector:main.site-main > div.site-main--wrap > div.layout-container > div.site-main--content snippet:<div class="site-main--content"> type:node] score:0.131652 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1035 height:275 left:0 right:412 top:760 width:412] lhId:page-5-IMG nodeLabel:Studierende auf dem Campus vor dem Audimax path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,1,DIV,0,ARTICLE,0,DIV,0,DIV,0,DIV,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,PICTURE,3,IMG selector:div > div.field > picture > img snippet:<img width="1260" height="840" loading="eager" fetchpriority="high" src="https://www.ruhr-uni-bochum.de/sites/default/files/styles/768s/public/2021…" alt="Studierende auf dem Campus vor dem Audimax"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:1213 height:168 left:0 right:412 top:1045 width:412] lhId:page-1-DIV nodeLabel:Infos für Erstsemester Neu an der Ruhr-Universität? In den ersten Tagen des S… path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,1,DIV,0,ARTICLE,0,DIV,0,DIV,0,DIV,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,DIV selector:div.rub-teaser > div.paragraph > div > div.grouped-elements snippet:<div class="grouped-elements"> type:node] score:0.002584 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1035 height:275 left:0 right:412 top:760 width:412] lhId:page-5-IMG nodeLabel:Studierende auf dem Campus vor dem Audimax path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,1,DIV,0,ARTICLE,0,DIV,0,DIV,0,DIV,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,PICTURE,3,IMG selector:div > div.field > picture > img snippet:<img width="1260" height="840" loading="eager" fetchpriority="high" src="https://www.ruhr-uni-bochum.de/sites/default/files/styles/768s/public/2021…" alt="Studierende auf dem Campus vor dem Audimax"> type:node]] map[cause:Web font extra:map[type:url value:https://www.ruhr-uni-bochum.de/themes/custom/rub/fonts/FlamaPro-Medium.woff]] map[cause:Web font extra:map[type:url value:https://www.ruhr-uni-bochum.de/themes/custom/rub/fonts/f6dc818d-560b-492b-8a95-e5fb445c15cf.woff2]] map[cause:Web font extra:map[type:url value:https://www.ruhr-uni-bochum.de/themes/custom/rub/fonts/610a9c94-45a4-4549-81df-a9307ddfd949.woff2]] map[cause:Web font extra:map[type:url value:https://www.ruhr-uni-bochum.de/themes/custom/rub/fonts/6a92fda6-9e6d-40b9-a93a-37e712a64599.woff2]] map[cause:Web font extra:map[type:url value:https://www.ruhr-uni-bochum.de/themes/custom/rub/fonts/Flama-Basic-A.woff]]] type:subitems]] map[node:map[boundingRect:map[bottom:65 height:35 left:350 right:385 top:30 width:35] lhId:page-3-DIV nodeLabel:header.site-header--wrap > div.site-header > div.layout-container > div.bar-menu path:1,HTML,1,BODY,2,DIV,0,DIV,1,HEADER,3,DIV,0,DIV,4,DIV selector:header.site-header--wrap > div.site-header > div.layout-container > div.bar-menu snippet:<div class="bar-menu"> type:node] score:0.000111 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1035 height:275 left:0 right:412 top:760 width:412] lhId:page-5-IMG nodeLabel:Studierende auf dem Campus vor dem Audimax path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,1,DIV,0,ARTICLE,0,DIV,0,DIV,0,DIV,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,PICTURE,3,IMG selector:div > div.field > picture > img snippet:<img width="1260" height="840" loading="eager" fetchpriority="high" src="https://www.ruhr-uni-bochum.de/sites/default/files/styles/768s/public/2021…" alt="Studierende auf dem Campus vor dem Audimax"> type:node]] map[cause:Web font extra:map[type:url value:https://www.ruhr-uni-bochum.de/themes/custom/rub/fonts/rub-web-icons.woff?v=2]]] type:subitems]]]

items: [map[node:map[type:text value:Total] score:0.140965] map[node:map[boundingRect:map[bottom:8489 height:7922 left:0 right:412 top:567 width:412] lhId:page-2-DIV nodeLabel:Built to change Gebaut, um zu verändern: Seit 60 Jahren treibt die Ruhr-Univer… path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,1,DIV selector:main.site-main > div.site-main--wrap > div.layout-container > div.site-main--content snippet:<div class="site-main--content"> type:node] score:0.140965 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1035 height:275 left:0 right:412 top:760 width:412] lhId:page-5-IMG nodeLabel:Studierende auf dem Campus vor dem Audimax path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,1,DIV,0,ARTICLE,0,DIV,0,DIV,0,DIV,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,PICTURE,3,IMG selector:div > div.field > picture > img snippet:<img width="1260" height="840" loading="eager" fetchpriority="high" src="https://www.ruhr-uni-bochum.de/sites/default/files/styles/768s/public/2021…" alt="Studierende auf dem Campus vor dem Audimax"> type:node]]] type:subitems]]]

items: [map[node:map[type:text value:Total] score:0.217655] map[node:map[boundingRect:map[bottom:8489 height:7922 left:0 right:412 top:567 width:412] lhId:page-2-DIV nodeLabel:Built to change Gebaut, um zu verändern: Seit 60 Jahren treibt die Ruhr-Univer… path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,1,DIV selector:main.site-main > div.site-main--wrap > div.layout-container > div.site-main--content snippet:<div class="site-main--content"> type:node] score:0.217655 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1035 height:275 left:0 right:412 top:760 width:412] lhId:page-5-IMG nodeLabel:Studierende auf dem Campus vor dem Audimax path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,1,DIV,0,ARTICLE,0,DIV,0,DIV,0,DIV,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,PICTURE,3,IMG selector:div > div.field > picture > img snippet:<img width="1260" height="840" loading="eager" fetchpriority="high" src="https://www.ruhr-uni-bochum.de/sites/default/files/styles/768s/public/2021…" alt="Studierende auf dem Campus vor dem Audimax"> type:node]]] type:subitems]]]

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.

Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:label label:Subpart valueType:text] map[key:duration label:Duration valueType:ms]]

items: [map[duration:217.9329990234375 label:Time to first byte subpart:timeToFirstByte] map[duration:6854.556000976562 label:Resource load delay subpart:resourceLoadDelay] map[duration:113.303 label:Resource load duration subpart:resourceLoadDuration] map[duration:20.714 label:Element render delay subpart:elementRenderDelay]]

lhId: page-0-VIDEO

nodeLabel: Momentaufnahmen aus dem Universitätsalltag

path: 1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,VIDEO

selector: div.paragraph > div.hero-banner-wrapper > div#rub-video-8950-5201 > video.VIMP_embed_video

snippet: <video class="VIMP_embed_video" style="width: 720px; height: 405px; max-height: 100vh; object-fit: contain;" disablepictureinpicture="true" controlslist="noremoteplayback nodownload noplaybackrate nofullscreen" crossorigin="anonymous" autoplay="autoplay" airplay="allow" x-webkit-airplay="allow" playsinline="" poster="https://video.ruhr-uni-bochum.de/cache/a7d5529448690fcbdbfcf58a22ad1622.we…" alt="Momentaufnahmen aus dem Universitätsalltag" loop="true">

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-VIDEO

nodeLabel: Momentaufnahmen aus dem Universitätsalltag

path: 1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,1,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,VIDEO

selector: div.paragraph > div.hero-banner-wrapper > div#rub-video-8950-5201 > video.VIMP_embed_video

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

value: no origins were preconnected

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

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.

	URL	Resource Size	Est Savings
Momentaufnahmen aus dem Universitätsalltag `div.paragraph > div.hero-banner-wrapper > div#rub-video-8950-5201 > video.VIMP_embed_video`	video.ruhr-uni-bochum.de/cache/a7d5529448690fcbdbfcf58a22ad1622.webp	110.8 KiB	52.2 KiB
Zwei Menschen auf Sesseln `div.paragraph > div.field > picture > img`	/sites/default/files/styles/768s/public/2026-04/2026_04_2...	49.8 KiB	12.1 KiB
Porträt der Forscherin Olga Matveieva `div.action-area > div.left > div.field > img.image-style-_50x550sc`	/sites/default/files/styles/750x550sc/public/2026-04/2026...	25.4 KiB	5.2 KiB

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.

URL	Protocol
www.ruhr-uni-bochum.de/de	http/1.1
www.ruhr-uni-bochum.de/themes/custom/rub/fonts/flamapro-basic.woff	http/1.1
www.ruhr-uni-bochum.de/themes/custom/rub/fonts/rub-web-icons.woff	http/1.1
www.ruhr-uni-bochum.de/themes/custom/rub/fonts/FlamaPro-Medium.woff	http/1.1
/themes/custom/rub/fonts/f6dc818d-560b-492b-8a95-e5fb445c...	http/1.1
/themes/custom/rub/fonts/610a9c94-45a4-4549-81df-a9307ddf...	http/1.1
/themes/custom/rub/fonts/6a92fda6-9e6d-40b9-a93a-37e712a6...	http/1.1
www.ruhr-uni-bochum.de/themes/custom/rub/fonts/Flama-Basic-A.woff	http/1.1
www.ruhr-uni-bochum.de/themes/custom/rub/logo.svg	http/1.1
www.ruhr-uni-bochum.de/themes/custom/rub/image/ua_ruhr_logo.svg	http/1.1
/sites/default/files/css/css_hMNrpJKl6AlrYo1LTh_wvcjs3UYL...	http/1.1
/sites/default/files/css/css_RhazXCXb2NBAL2EHrV9LXzDXI6bq...	http/1.1
/sites/default/files/css/css_fPirha2xT8TzhueCnKA_1QHLr6Fw...	http/1.1
/sites/default/files/styles/768s/public/2021-01/studium_u...	http/1.1
/themes/custom/rub/dist/lib/modernizr.custom.min.js?v=3.3.1	http/1.1
/sites/default/files/js/js_04Vs-H9jK7kZ8dPGYnFdD2qpd6T7Ej...	http/1.1
www.ruhr-uni-bochum.de/core/assets/vendor/loadjs/loadjs.min.js?v=4.3.0	http/1.1
/sites/default/files/js/js_Or69rxs_88oGVinF3LTmYord3SV3R6...	http/1.1
/sites/default/files/js/js_EUCNs45PTfsdslOEV9ZTS1ILgIWPLK...	http/1.1
/sites/default/files/styles/330x220sc/public/2025-08/Logo...	http/1.1
/sites/default/files/styles/750x550sc/public/2026-04/2026...	http/1.1
/sites/default/files/styles/768s/public/2026-04/2026_04_2...	http/1.1
/sites/default/files/styles/768s/public/2026-04/2026_04_2...	http/1.1
/sites/default/files/styles/162x162sc/public/2018-02/Icon...	http/1.1
/sites/default/files/styles/330x220sc/public/2026-04/2026...	http/1.1
/sites/default/files/styles/330x220sc/public/2024-04/pres...	http/1.1
/sites/default/files/styles/330x220sc/public/imported_ima...	http/1.1
www.ruhr-uni-bochum.de/themes/custom/rub/fonts/rub-web-icons.woff?v=2	http/1.1
www.ruhr-uni-bochum.de/de/session/token	http/1.1
www.ruhr-uni-bochum.de/themes/custom/rub/favicon.ico	http/1.1
/de/rest/1.0/main_navigation?i=34300&c=2ab45fa3c9abfd8dd7...	http/1.1
/de/rest/1.0/main_navigation?i=34302&c=f4b484d02322f1c6f4...	http/1.1
/de/rest/1.0/main_navigation?i=34304&c=e6bb88ce42e5b021f0...	http/1.1
/de/rest/1.0/main_navigation?i=34299&c=8d6c0dbcf14382e755...	http/1.1
/de/rest/1.0/main_navigation?i=34301&c=15b98c5a5c220910f2...	http/1.1
/de/rest/1.0/main_navigation?i=34303&c=b0793768b1eafe1c9f...	http/1.1

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: 753 ms

URL	Time Spent
ruhr-uni-bochum.de/	753 ms
www.ruhr-uni-bochum.de/de	0.0 ms

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS

Why this matters

Performance issues directly impact user engagement and conversion rates.

Element	Layout shift score
Built to change Gebaut, um zu verändern: Seit 60 Jahren treibt die Ruhr-Univer… `main.site-main > div.site-main--wrap > div.layout-container > div.site-main--content`	0.218
Built to change Gebaut, um zu verändern: Seit 60 Jahren treibt die Ruhr-Univer… `main.site-main > div.site-main--wrap > div.layout-container > div.site-main--content`	0.141
Built to change Gebaut, um zu verändern: Seit 60 Jahren treibt die Ruhr-Univer… `main.site-main > div.site-main--wrap > div.layout-container > div.site-main--content`	0.132
Infos für Erstsemester Neu an der Ruhr-Universität? In den ersten Tagen des S… `div.rub-teaser > div.paragraph > div > div.grouped-elements`	0.003
header.site-header--wrap > div.site-header > div.layout-container > div.bar-menu `header.site-header--wrap > div.site-header > div.layout-container > div.bar-menu`	0.000

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

Diagnostics

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: 750 ms 120.9 KiB

URL	Transfer Size	Est Savings
/sites/default/files/css/css_RhazXCXb2NBAL2EHrV9LXzDXI6bq...	63.5 KiB	55.3 KiB
/sites/default/files/css/css_fPirha2xT8TzhueCnKA_1QHLr6Fw...	55.0 KiB	55.0 KiB
/sites/default/files/css/css_hMNrpJKl6AlrYo1LTh_wvcjs3UYL...	10.8 KiB	10.7 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: 1.1 s 186.4 KiB

URL	Transfer Size	Est Savings
/sites/default/files/js/js_04Vs-H9jK7kZ8dPGYnFdD2qpd6T7Ej...	139.4 KiB	62.6 KiB
/sites/default/files/js/js_Or69rxs_88oGVinF3LTmYord3SV3R6...	95.2 KiB	54.2 KiB
video.ruhr-uni-bochum.de/js/mediaEmbed.js.php	53.2 KiB	39.3 KiB
statistic.ruhr-uni-bochum.de/matomo.js	45.0 KiB	30.3 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.

URL	Transfer Size
/getMedium/364a3d63c2374aca9b97c93a5d51fb68.m4v?177689397...	3.1 MiB
/sites/default/files/js/js_04Vs-H9jK7kZ8dPGYnFdD2qpd6T7Ej...	139.9 KiB
video.ruhr-uni-bochum.de/cache/a7d5529448690fcbdbfcf58a22ad1622.webp	111.0 KiB
/sites/default/files/js/js_Or69rxs_88oGVinF3LTmYord3SV3R6...	95.9 KiB
/sites/default/files/css/css_RhazXCXb2NBAL2EHrV9LXzDXI6bq...	64.1 KiB
/sites/default/files/styles/768s/public/2021-01/studium_u...	55.9 KiB
/sites/default/files/css/css_fPirha2xT8TzhueCnKA_1QHLr6Fw...	55.6 KiB
video.ruhr-uni-bochum.de/js/mediaEmbed.js.php	53.6 KiB
/sites/default/files/styles/768s/public/2026-04/2026_04_2...	50.5 KiB
www.ruhr-uni-bochum.de/themes/custom/rub/fonts/Flama-Basic-A.woff	46.8 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
UA Ruhr `div.ua-ruhr-menu > div.wrap > a > img`	www.ruhr-uni-bochum.de/themes/custom/rub/image/ua_ruhr_logo.svg
Startseite `div.layout-container > div#block-sitebranding-header > a.site-logo > img`	www.ruhr-uni-bochum.de/themes/custom/rub/logo.svg
Startseite `div.context-groups > div#block-system-branding-block > a.site-logo > img`	www.ruhr-uni-bochum.de/themes/custom/rub/logo.svg

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

●Max Potential First Input Delay 120 ms

●Optimize DOM size

●Font display

●Forced reflow

●Render blocking requests

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●JavaScript execution time 0.6 s

●Minimizes main-thread work 1.8 s

●Avoid long main-thread tasks 5 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 40 ms

●Server Backend Latencies 420 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 40 ms

○INP breakdown

○User Timing marks and measures

○Avoid non-composited animations

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.

Names and labels

Including a skip link can help users skip to the main content to save time. Learn more about skip links.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Menu toolbar `nav.fast-navigation > ul.fast-navigation__list > li.fast-navigation__item > a.visually-hidden`

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

○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.

●ARIA attributes are used as specified for the element's role

●`[aria-hidden="true"]` elements do not contain focusable descendents

●Elements use only permitted ARIA attributes

●Background and foreground colors have a sufficient contrast ratio

●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

●Document has a main landmark.

●Deprecated ARIA roles were not used

●`<video>` elements contain a `<track>` element with `[kind="captions"]`

○`[accesskey]` values are unique

○`button`, `link`, and `menuitem` elements have accessible names

○Elements with `role="dialog"` or `role="alertdialog"` have accessible names.

○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

○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.

100

Best Practices

●Uses HTTPS

●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

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

●No browser errors logged to the console

●No issues in the `Issues` panel in Chrome Devtools

●Ensure CSP is effective against XSS attacks

●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

○Use a strong HSTS policy

○Mitigate clickjacking with XFO or CSP

100

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.

○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

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`