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Lighthouse Desktop

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

Audit breakdown by category with detailed findings.

99

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.

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

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.

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
stackoverflow.com/Content/shared/chrome/chrome.css?v=764504b195d8604800.0 s98.9 KiB
/cdn-cgi/challenge-platform/h/b/scripts/jsd/0b8fb825cb67/...14400.0 s11.5 KiB
/avatar/10128c971dfa3ca3d89f471b693c9d72?s=36&d=identicon...300.0 s2.6 KiB
/avatar/f12a0330c5264e0c0872cf83898e0059?s=36&d=identicon...300.0 s2.4 KiB
/avatar/efdd0371ee7b983ab3b858ea92653aeb?s=36&d=identicon...300.0 s2.4 KiB
/avatar/9d36c6c0fe72160847d8aff404d9f1a0?s=36&d=identicon...300.0 s2.3 KiB
/avatar/96f5e5d858f1562ac8075c2664451b3b?s=36&d=identicon...300.0 s2.1 KiB
/avatar/d764dae6d3b6b39bc8ff40e28367d78a?s=36&d=identicon...300.0 s2.1 KiB
/avatar/8bfaa20f8775b87a2c0a6d9f4193ecbb?s=36&d=identicon...300.0 s2.0 KiB
/avatar/ab85c6b652a16b8135438e80cf480c48?s=36&d=identicon...300.0 s2.0 KiB
/avatar/df1d710f79509457b8603d60608772c8?s=36&d=identicon...300.0 s1.9 KiB
/avatar/168f7b509dd534671cb52c7ff58a6cf6?s=36&d=identicon...300.0 s1.7 KiB
/avatar/2a2941970f141aad669d13375dc57c4f?s=36&d=identicon...300.0 s1.6 KiB
/avatar/e3887f18263b27e21575a5912b39a006?s=36&d=identicon...300.0 s1.6 KiB
cdn.sstatic.net/stackexchange/all.css?v=db31a2669ca3604800.0 s15.0 KiB
/avatar/e301b767390b98cb298cd04ee196ac58?s=36&d=identicon...300.0 s1.6 KiB
/avatar/03508d221da4d3ebb99c724e19370b55?s=36&d=identicon...300.0 s1.6 KiB
/avatar/31f2b9cfa1cd901e508101b38d1af8ff?s=36&d=identicon...300.0 s1.5 KiB
/avatar/e8458cd805d568cfbc85636614d9d098?s=36&d=identicon...300.0 s1.5 KiB
/avatar/58c3cb5e1dac8d62442514f34ab84a0e?s=36&d=identicon...300.0 s1.3 KiB
/avatar/456b30a6c93001f930a726ff05217518?s=36&d=identicon...300.0 s1.3 KiB
/avatar/29221d8b990c741f510ddddcb67ec47e?s=36&d=identicon...300.0 s1.2 KiB
cdn.sstatic.net/stackexchange/Js/topbar.js?v=b2367277c351604800.0 s11.4 KiB
cdn.sstatic.net/stackexchange/Js/master.js?v=ef8b6ed08310604800.0 s10.4 KiB
cdn.sstatic.net/stackexchange/Img/se-logo.png?v=8f7dca5b94db604800.0 s4.7 KiB
/a-/AOh14GiU9JJ1lMC8Ux8lye9FUkCF46ri4wL2hfMtMERbNA=k-s3686400.0 s1.2 KiB
puzzling.stackexchange.com/Content/Sites/puzzling/Img/icon-48.png604800.0 s4.0 KiB
stackexchange.com/Content/Img/hero/bubble.png604800.0 s3.3 KiB
stackexchange.com/Content/Img/hero/check.png604800.0 s2.9 KiB
mathoverflow.net/Content/Sites/mathoverflow/Img/icon-48.png604800.0 s2.9 KiB
mathematica.stackexchange.com/Content/Sites/mathematica/Img/icon-48.png604800.0 s2.3 KiB
electronics.stackexchange.com/Content/Sites/electronics/Img/icon-48.png604800.0 s2.3 KiB
worldbuilding.stackexchange.com/Content/Sites/worldbuilding/Img/icon-48.png604800.0 s2.0 KiB
cdn.sstatic.net/stackexchange/Js/universal-login.js?v=30968200101f604800.0 s2.0 KiB
askubuntu.com/Content/Sites/askubuntu/Img/favicon.ico604800.0 s2.0 KiB
crafts.stackexchange.com/Content/Sites/crafts/Img/icon-48.png604800.0 s1.9 KiB
math.stackexchange.com/Content/Sites/math/Img/favicon.ico604800.0 s1.7 KiB
space.stackexchange.com/Content/Sites/space/Img/icon-48.png604800.0 s1.7 KiB
politics.stackexchange.com/Content/Sites/politics/Img/icon-48.png604800.0 s1.6 KiB
matheducators.stackexchange.com/Content/Sites/matheducators/Img/icon-48.png604800.0 s1.5 KiB
electronics.stackexchange.com/Content/Sites/electronics/Img/favicon.ico604800.0 s1.5 KiB
unix.stackexchange.com/Content/Sites/unix/Img/favicon.ico604800.0 s1.5 KiB
law.stackexchange.com/Content/Sites/law/Img/icon-48.png604800.0 s1.4 KiB
tex.stackexchange.com/Content/Sites/tex/Img/icon-48.png604800.0 s1.3 KiB
scifi.stackexchange.com/Content/Sites/scifi/Img/icon-48.png604800.0 s1.3 KiB
superuser.com/Content/Sites/superuser/Img/favicon.ico604800.0 s1.3 KiB
lh3.googleusercontent.com/a/ALm5wu2ZKm-HZQlbttbBrwGc1C9gtZ7Ij-K1hAqD9WhN=k-s3686400.0 s334 B
english.stackexchange.com/Content/Sites/english/Img/favicon.ico604800.0 s1.3 KiB
stackoverflow.com/Content/Sites/stackoverflow/Img/favicon.ico604800.0 s1.2 KiB
ru.stackoverflow.com/Content/Sites/ru/Img/favicon.ico604800.0 s1.2 KiB
superuser.com/Content/Sites/superuser/Img/icon-48.png604800.0 s1.2 KiB
serverfault.com/Content/Sites/serverfault/Img/favicon.ico604800.0 s1.1 KiB
stackexchange.com/Content/Img/hero/vote.png604800.0 s1.0 KiB
math.stackexchange.com/Content/Sites/math/Img/icon-48.png604800.0 s1.0 KiB
philosophy.stackexchange.com/Content/Sites/philosophy/Img/icon-48.png604800.0 s977 B
physics.stackexchange.com/Content/Sites/physics/Img/icon-48.png604800.0 s876 B
stackoverflow.com/Content/Sites/stackoverflow/Img/icon-48.png604800.0 s866 B
pm.stackexchange.com/Content/Sites/pm/Img/apple-touch-icon.png604800.0 s810 B
academia.stackexchange.com/Content/Sites/academia/Img/icon-48.png604800.0 s774 B
rpg.stackexchange.com/Content/Sites/rpg/Img/icon-48.png604800.0 s767 B
meta.stackexchange.com/Content/Sites/stackexchangemeta/Img/favicon.ico604800.0 s709 B
history.stackexchange.com/Content/Sites/history/Img/icon-48.png604800.0 s577 B
english.stackexchange.com/Content/Sites/english/Img/icon-48.png604800.0 s556 B
stackexchange.com/Content/Img/hero/close.png604800.0 s464 B
crypto.stackexchange.com/Content/Sites/crypto/Img/icon-48.png604800.0 s387 B

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
Italian Philosopher div.module > div.userDetails > a > img.bar-sm
i.sstatic.net/xajrG.png?s=644.8 KiB4.6 KiB

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

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: 60 ms 105.2 KiB

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 10.5 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
Voting arrows div.row > div > div.column > img
stackexchange.com/Content/Img/hero/vote.png
Speech bubbles div.row > div > div.column > img
stackexchange.com/Content/Img/hero/bubble.png
checkmark div.row > div > div.column > img
stackexchange.com/Content/Img/hero/check.png
close div.hero-box > div.close > a > img
stackexchange.com/Content/Img/hero/close.png

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

Layout shift culprits
Document request latency
Optimize DOM size
Font display
Forced reflow
LCP breakdown
Modern HTTP
Optimize viewport for mobile
Time to Interactive 1.2 s
Max Potential First Input Delay 60 ms
Minify CSS
Reduce unused JavaScript
Avoids enormous network payloads Total size was 340 KiB
JavaScript execution time 0.1 s
Minimizes main-thread work 0.6 s
Avoid long main-thread tasks 1 long task found
Page didn't prevent back/forward cache restoration
Network Requests
Network Round Trip Times 50 ms
Server Backend Latencies 130 ms
Tasks
Diagnostics
Metrics
Screenshot Thumbnails
Final Screenshot
Script Treemap Data
Resources Summary
Avoid multiple page redirects
Initial server response time was short Root document took 150 ms
INP breakdown
LCP request discovery
User Timing marks and measures
Avoid non-composited animations
Avoid large layout shifts
80

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

Some ARIA roles have required attributes that describe the state of the element to screen readers. Learn more about roles and required attributes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Search div.s-topbar--container > form#search > div.s-topbar--searchbar--input-group > input.s-input

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
hot div#mainArea > div.subheader > div.tabs > a.youarehere
4 answers | asked 10 hours ago by vsz on scifi div.question-container > div.question > div.metaInfo > span.va-middle
by vsz on div.question > div.metaInfo > span.va-middle > span.owner
4 answers | asked 13 hours ago by Erwann on tex div.question-container > div.question > div.metaInfo > span.va-middle
by Erwann on div.question > div.metaInfo > span.va-middle > span.owner
4 answers | asked 18 hours ago by pie on matheducators div.question-container > div.question > div.metaInfo > span.va-middle
by pie on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked 22 hours ago by Rafał Mach on mathoverflow div.question-container > div.question > div.metaInfo > span.va-middle
by Rafał Mach on div.question > div.metaInfo > span.va-middle > span.owner
1 answers | asked 9 hours ago by RidiculousRichard on space div.question-container > div.question > div.metaInfo > span.va-middle
by RidiculousRichard on div.question > div.metaInfo > span.va-middle > span.owner
1 answers | asked 17 hours ago by honestSalami on history div.question-container > div.question > div.metaInfo > span.va-middle
by honestSalami on div.question > div.metaInfo > span.va-middle > span.owner
3 answers | asked 20 hours ago by Sebastiano on tex div.question-container > div.question > div.metaInfo > span.va-middle
by Sebastiano on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked yesterday by Mike on rpg div.question-container > div.question > div.metaInfo > span.va-middle
by Mike on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked yesterday by Italian Philosopher on politics div.question-container > div.question > div.metaInfo > span.va-middle
by Italian Philosopher on div.question > div.metaInfo > span.va-middle > span.owner
3 answers | asked 14 hours ago by Rio C on puzzling div.question-container > div.question > div.metaInfo > span.va-middle
by Rio C on div.question > div.metaInfo > span.va-middle > span.owner
1 answers | asked yesterday by Raj on scifi div.question-container > div.question > div.metaInfo > span.va-middle
by Raj on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked 22 hours ago by karlh on tex div.question-container > div.question > div.metaInfo > span.va-middle
by karlh on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked 21 hours ago by TomY on physics div.question-container > div.question > div.metaInfo > span.va-middle
by TomY on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked 18 hours ago by Trevor on english div.question-container > div.question > div.metaInfo > span.va-middle
by Trevor on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked 9 hours ago by Zachary Barbanell on crypto div.question-container > div.question > div.metaInfo > span.va-middle
by Zachary Barbanell on div.question > div.metaInfo > span.va-middle > span.owner
3 answers | asked 22 hours ago by Alma Arjuna on math div.question-container > div.question > div.metaInfo > span.va-middle
by Alma Arjuna on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked yesterday by Rajorshi Chattopadhyay on academia div.question-container > div.question > div.metaInfo > span.va-middle
by Rajorshi Chattopadhyay on div.question > div.metaInfo > span.va-middle > span.owner
1 answers | asked 12 hours ago by robertspierre on superuser div.question-container > div.question > div.metaInfo > span.va-middle
by robertspierre on div.question > div.metaInfo > span.va-middle > span.owner
6 answers | asked Apr 18 at 15:36 by Dmyt on worldbuilding div.question-container > div.question > div.metaInfo > span.va-middle
by Dmyt on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked yesterday by Mike on rpg div.question-container > div.question > div.metaInfo > span.va-middle
by Mike on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked yesterday by Jay Bee on space div.question-container > div.question > div.metaInfo > span.va-middle
by Jay Bee on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked 18 hours ago by Student_Number_249812341 on physics div.question-container > div.question > div.metaInfo > span.va-middle
by Student_Number_249812341 on div.question > div.metaInfo > span.va-middle > span.owner
4 answers | asked 2 days ago by qwerty on mathematica div.question-container > div.question > div.metaInfo > span.va-middle
by qwerty on div.question > div.metaInfo > span.va-middle > span.owner
7 answers | asked 2 days ago by Alex on electronics div.question-container > div.question > div.metaInfo > span.va-middle
by Alex on div.question > div.metaInfo > span.va-middle > span.owner
1 answers | asked 23 hours ago by Howard Hinnant on stackoverflow div.question-container > div.question > div.metaInfo > span.va-middle
by Howard Hinnant on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked yesterday by dsollen on law div.question-container > div.question > div.metaInfo > span.va-middle
by dsollen on div.question > div.metaInfo > span.va-middle > span.owner
9 answers | asked 2 days ago by Syed on philosophy div.question-container > div.question > div.metaInfo > span.va-middle
by Syed on div.question > div.metaInfo > span.va-middle > span.owner
4 answers | asked 2 days ago by Rean on academia div.question-container > div.question > div.metaInfo > span.va-middle
by Rean on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked 15 hours ago by Vincent on tex div.question-container > div.question > div.metaInfo > span.va-middle
by Vincent on div.question > div.metaInfo > span.va-middle > span.owner
2 answers | asked 20 hours ago by Joseph Rose on crafts div.question-container > div.question > div.metaInfo > span.va-middle
by Joseph Rose on div.question > div.metaInfo > span.va-middle > span.owner
per page div#mainArea > div#question-list > div.page-sizer > span.page-numbers
6.5k div.featured-site > div.site-stats > div.stats-container > div.stats
20k div.featured-site > div.site-stats > div.stats-container > div.stats
97% div.featured-site > div.site-stats > div.stats-container > div.stats
hot questions feed section#content > div.contentWrapper > div#feed-link > a
About div.site-footer--col > ul.-list > li > a.js-gps-track
Contact div.site-footer--col > ul.-list > li > a.js-gps-track
Feedback div.site-footer--col > ul.-list > li > a.js-gps-track
Stack Overflow div.site-footer--col > ul.-list > li > a.js-gps-track
Stack Internal div.site-footer--col > ul.-list > li > a.js-gps-track
Stack Data Licensing div.site-footer--col > ul.-list > li > a.js-gps-track
Stack Ads div.site-footer--col > ul.-list > li > a.js-gps-track
Press div.site-footer--col > ul.-list > li > a.js-gps-track
Legal div.site-footer--col > ul.-list > li > a.js-gps-track
Privacy Policy div.site-footer--col > ul.-list > li > a.js-gps-track
Terms of Service div.site-footer--col > ul.-list > li > a.js-gps-track
Cookie Settings div.site-footer--col > ul.-list > li#consent-footer-link > button.s-btn
Cookie Policy div.site-footer--col > ul.-list > li > a.js-gps-track
Technology div > ul.-list > li > a.-link
Culture & recreation div > ul.-list > li > a.-link
Life & arts div > ul.-list > li > a.-link
Science div > ul.-list > li > a.-link
Professional div > ul.-list > li > a.-link
Business div > ul.-list > li > a.-link
API div > ul.-list > li.mt16 > a.-link
Data div > ul.-list > li > a.-link
Blog div.site-footer--copyright > ul.-list > li > a.js-gps-track
Facebook div.site-footer--copyright > ul.-list > li > a.-link
Twitter div.site-footer--copyright > ul.-list > li > a.-link
LinkedIn div.site-footer--copyright > ul.-list > li > a.-link
Instagram div.site-footer--copyright > ul.-list > li > a.-link
Site design / logo © 2026 Stack Exchange Inc; div.site-footer--container > div.site-footer--copyright > p.md:mb0 > span
user contributions licensed under div.site-footer--container > div.site-footer--copyright > p.md:mb0 > span
CC BY-SA div.site-footer--container > div.site-footer--copyright > p.md:mb0 > a.-link
rev 2026.4.21.42306 div.site-footer--container > div.site-footer--copyright > p.md:mb0 > span#svnrev

These are opportunities to improve the legibility of your content.

Navigation

Properly ordered headings that do not skip levels convey the semantic structure of the page, making it easier to navigate and understand when using assistive technologies. Learn more about heading order.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Stack Exchange Q&A communities are different. Here's how: div.hero-box > div.row > div.text > h3.title
STACK EXCHANGE div.site-footer--container > nav.site-footer--nav > div.site-footer--col > h5.-title

These are opportunities to improve keyboard navigation in your application.

Names and labels

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.wrapper > header.s-topbar > div.s-topbar--container > a.s-topbar--logo div.wrapper > header.s-topbar > div.s-topbar--container > a.s-topbar--logo

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.

Tables and lists

Screen readers require list items (`<li>`) to be contained within a parent `<ul>`, `<ol>` or `<menu>` to be announced properly. Learn more about proper list structure.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Tour header.s-topbar > div.s-topbar--container > ol.s-navigation > li
About Us header.s-topbar > div.s-topbar--container > ol.s-navigation > li
Meta header.s-topbar > div.s-topbar--container > ol.s-navigation > li

These are opportunities to improve the experience of reading tabular or list data using assistive technology, like a screen reader.

Best practices

One main landmark helps screen reader users navigate a web page. Learn more about landmarks.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html html

These items highlight common accessibility best practices.

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]` 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
Form elements have associated labels
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
Document has a `<title>` element
`<html>` element has a `[lang]` attribute
`<html>` element has a valid value for its `[lang]` attribute
Links are distinguishable without relying on color.
Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
Touch targets have sufficient size and spacing.
Skip links are focusable.
Deprecated ARIA roles were not used
Uses ARIA roles only on compatible elements
Image elements do not have `[alt]` attributes that are redundant text.
Identical links have the same purpose.
`[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
The document does not use `<meta http-equiv="refresh">`
`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
`<object>` elements have alternate text
Select elements have associated label elements.
No element has a `[tabindex]` value greater than 0
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.
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.
81

Best Practices

General

Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Deprecation / WarningSource
SharedStorage
StorageType.persistent is deprecated. Please use standardized navigator.storage instead.
Fledge
Uses HTTPS
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
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
91

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.

Content Best Practices

Descriptive link text helps search engines understand your content. Learn how to make links more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Link destinationLink Text
stackexchange.com/tourLearn more

Format your HTML in a way that enables crawlers to better understand your app’s content.

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 are crawlable
Image elements have `[alt]` attributes
Document has a valid `hreflang`
robots.txt is valid
Document has a valid `rel=canonical`

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