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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.

54

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.

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
d35aaqx5ub95lt.cloudfront.net/vendor/68d22534874c554b0c9ebabea379fc60.woff255 ms
fonts.gstatic.com/s/roboto/v48/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff245 ms
d35aaqx5ub95lt.cloudfront.net/fonts/642e24bb0295f3aee4dedcd8eecd8007.woff25.0 ms
d35aaqx5ub95lt.cloudfront.net/fonts/a96f1b78ebf295556c0e9500cde6dd64.woff25.0 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:3.891 source:map[column:34909 line:7 type:source-location url:https://cdn.cookielaw.org/scripttemplates/202404.1.0/otBannerSdk.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:57.302 source:map[type:text value:[unattributed]]] map[reflowTime:3.294 source:map[column:258333 line:6 type:source-location url:https://cdn.cookielaw.org/scripttemplates/202404.1.0/otBannerSdk.js urlProvider:network]] map[reflowTime:0.117 source:map[column:258677 line:6 type:source-location url:https://cdn.cookielaw.org/scripttemplates/202404.1.0/otBannerSdk.js urlProvider:network]] map[reflowTime:0.48 source:map[column:146929 line:6 type:source-location url:https://cdn.cookielaw.org/scripttemplates/202404.1.0/otBannerSdk.js urlProvider:network]]]

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:680.143 label:Time to first byte subpart:timeToFirstByte] map[duration:1874.218 label:Element render delay subpart:elementRenderDelay]]
lhId: page-0-DIV
nodeLabel: We and third parties, such as our advertising partners and service providers, u…
path: 1,HTML,1,BODY,5,DIV,1,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,DIV,1,DIV
selector: div.ot-sdk-row > div#onetrust-group-container > div#onetrust-policy > div#onetrust-policy-text
snippet: <div id="onetrust-policy-text">

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

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
cdn.cookielaw.org/scripttemplates/otSDKStub.js9.1 KiB262 ms
d35aaqx5ub95lt.cloudfront.net/css/app-12b7bcea.css16.3 KiB
d35aaqx5ub95lt.cloudfront.net/css/6057-7317442d.css10.4 KiB205 ms

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
cdn.cookielaw.org/scripttemplates/202404.1.0/otBannerSdk.js86400.0 s108.9 KiB
cdn.cookielaw.org/scripttemplates/otSDKStub.js86400.0 s9.1 KiB
www.gstatic.com/recaptcha/api2/logo_48.png604800.0 s2.3 KiB

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: 491 ms
URLTime Spent
duolingo.com/491 ms
www.duolingo.com/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

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: 810 ms 804.0 KiB
URLTransfer SizeEst Savings
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js361.8 KiB176.9 KiB
d35aaqx5ub95lt.cloudfront.net/js/app-6c532e98.js315.8 KiB175.0 KiB
d35aaqx5ub95lt.cloudfront.net/js/6057-b2849109.js237.0 KiB138.1 KiB
www.googletagmanager.com/gtm.js?id=GTM-TX6Z97C167.0 KiB89.5 KiB
accounts.google.com/gsi/client95.4 KiB75.1 KiB
cdn.cookielaw.org/scripttemplates/202404.1.0/otBannerSdk.js108.6 KiB67.1 KiB
www.googletagmanager.com/gtag/js?id=AW-728842606&cx=c&gtm=4e64e1137.2 KiB61.1 KiB
d35aaqx5ub95lt.cloudfront.net/js/5314-33cb86aa.js45.4 KiB21.2 KiB

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTotal CPU TimeScript EvaluationScript Parse
d35aaqx5ub95lt.cloudfront.net/js/5314-33cb86aa.js7.0 s3.9 s2.8 ms
www.duolingo.com/3.8 s2.0 ms1.5 ms
Unattributable786 ms29 ms0.0 ms
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js493 ms440 ms17 ms
d35aaqx5ub95lt.cloudfront.net/js/6057-b2849109.js486 ms380 ms16 ms
d35aaqx5ub95lt.cloudfront.net/js/app-6c532e98.js446 ms384 ms23 ms
www.googletagmanager.com/gtag/js?id=AW-728842606&cx=c&gtm=4e64e163 ms51 ms11 ms
www.googletagmanager.com/gtm.js?id=GTM-TX6Z97C61 ms48 ms12 ms

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 Evaluation5.4 s
Style & Layout3.3 s
Other3.1 s
Rendering1.3 s
Garbage Collection122 ms
Script Parsing & Compilation121 ms
Parse HTML & CSS10.0 ms

Many navigations are performed by going back to a previous page, or forwards again. The back/forward cache (bfcache) can speed up these return navigations. Learn more about the bfcache

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failure reasonFailure type
The page has an unload handler in the main frame.Actionable
Pages with cache-control:no-store header cannot enter back/forward cache.Actionable
Pages whose main resource has cache-control:no-store cannot enter back/forward cache.Not actionable
Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header.Not actionable

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: 0.0 ms 13.1 KiB
URLTransfer SizeEst Savings
d35aaqx5ub95lt.cloudfront.net/css/app-12b7bcea.css16.0 KiB13.1 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.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js362.3 KiB
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js361.9 KiB
d35aaqx5ub95lt.cloudfront.net/js/app-6c532e98.js316.8 KiB
d35aaqx5ub95lt.cloudfront.net/js/6057-b2849109.js237.5 KiB
/lottie/splash/82f26795696242931a7b905b4918eb1e.json169.4 KiB
www.googletagmanager.com/gtm.js?id=GTM-TX6Z97C167.4 KiB
/lottie/splash/e97b1cde32a58c629a0193eea36ddaab.json137.5 KiB
www.googletagmanager.com/gtag/js?id=AW-728842606&cx=c&gtm=4e64e1137.3 KiB
/images/splash/lottie/833a22b2834050d139f266a29899bb00.svg121.7 KiB
cdn.cookielaw.org/scripttemplates/202404.1.0/otBannerSdk.js108.9 KiB

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

●Layout shift culprits
●Optimize DOM size
●Improve image delivery
●Modern HTTP
●Optimize viewport for mobile
●Minify CSS
●Minify JavaScript
●Avoid long main-thread tasks 4 long tasks found
●Image elements have explicit `width` and `height`
●Network Requests
●Network Round Trip Times 100 ms
●Server Backend Latencies 110 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 140 ms
○INP breakdown
○LCP request discovery
○User Timing marks and measures
○Avoid non-composited animations
○Avoid large layout shifts
86

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.

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
SITE LANGUAGE: ENGLISH nav.lZqWH > div.tFegI > button._1gEmM > span._9lHjd
ENGLISH ul._399s9 > li > a._1nZQi > span._2qfTm
SPANISH ul._399s9 > li > a._1nZQi > span._2qfTm
FRENCH ul._399s9 > li > a._1nZQi > span._2qfTm
GERMAN ul._399s9 > li > a._1nZQi > span._2qfTm
ITALIAN ul._399s9 > li > a._1nZQi > span._2qfTm
PORTUGUESE ul._399s9 > li > a._1nZQi > span._2qfTm
MATH ul._399s9 > li > a._1nZQi > span._2qfTm
CHESS ul._399s9 > li > a._1nZQi > span._2qfTm
free. fun. effective. section.uU0-M > section._3k9io > div._2Yq-n > h2._3X-2C
Learning with Duolingo is fun, and research shows that it works! With quick, bi… section._3k9io > div._2Yq-n > p.KsAV5 > span
research shows that it works div._2Yq-n > p.KsAV5 > span > a._1F7oE
backed by science section.uU0-M > section._36L7f > div._2Yq-n > h2._3X-2C
We use a combination of research-backed teaching methods and delightful content… section.uU0-M > section._36L7f > div._2Yq-n > p.KsAV5
stay motivated section.uU0-M > section._3k9io > div._2Yq-n > h2._3X-2C
We make it easy to form a habit of language learning with game-like features, f… section.uU0-M > section._3k9io > div._2Yq-n > p.KsAV5
personalized learning section.uU0-M > section._36L7f > div._2Yq-n > h2._3X-2C
Combining the best of AI and language science, lessons are tailored to help you… section.uU0-M > section._36L7f > div._2Yq-n > p.KsAV5
duolingo english test div._2Yq-n > h2._3X-2C > span > span
Our convenient, fast, and affordable English test integrates the latest assessm… section._3dG3I > section._3k9io > div._2Yq-n > p.KsAV5
duolingo for schools section._3dG3I > section._36L7f > div._2Yq-n > h2._3X-2C
Teachers, we’re here to help you! Our free tools support your students as they … section._3dG3I > section._36L7f > div._2Yq-n > p.KsAV5
duolingo abc section._3dG3I > section._3k9io > div._2Yq-n > h2._3X-2C
From language to literacy! With fun phonics lessons and delightful stories, Duo… section._3dG3I > section._3k9io > div._2Yq-n > p.KsAV5
About us div.kWIKU > div._2zjY4 > div > div._30Vi6
Courses div > ul > li > a
Mission div > ul > li > a
Approach div > ul > li > a
Efficacy div > ul > li > a
Duolingo Handbook div > ul > li > a
Research div > ul > li > a
Careers div > ul > li > a
Brand guidelines div > ul > li > a
Store div > ul > li > a
Press div > ul > li > a
Investors div > ul > li > a
Contact us div > ul > li > a
Products div.kWIKU > div._2zjY4 > div > div._30Vi6
Duolingo div > ul > li > a
Duolingo for Schools div > ul > li > a
Duolingo English Test div > ul > li > a
Podcast div > ul > li > a
Duolingo for Business div > ul > li > a
Super Duolingo div > ul > li > a
Gift Super Duolingo div > ul > li > a
Duolingo Max div > ul > li > a
Apps div.kWIKU > div._2zjY4 > div > div._30Vi6
Duolingo for Android div > ul > li > a
Duolingo for iOS div > ul > li > a
Help and support div.kWIKU > div._2zjY4 > div > div._30Vi6
Duolingo FAQs div > ul > li > a
Schools FAQs div > ul > li > a
Duolingo English Test FAQs div > ul > li > a
Status div > ul > li > a
Privacy and terms div.kWIKU > div._2zjY4 > div > div._30Vi6
Community guidelines div > ul > li > a
Terms div > ul > li > a
Privacy div > ul > li > a
Do Not Sell or Share My Personal Information div > ul > li > a
Social div.kWIKU > div._2zjY4 > div > div._30Vi6
Blog div > ul > li > a
Instagram div > ul > li > a
TikTok div > ul > li > a
Twitter div > ul > li > a
YouTube div > ul > li > a
LinkedIn div > ul > li > a
Site language: div.qO_UG > footer._1nNuk > div.-Dahb > div._1LLyK
العربية div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
বাংলা div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Čeština div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Deutsch div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Ελληνικά div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
English div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Español div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Français div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
हिंदी div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Magyar div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Bahasa Indonesia div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Italiano div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
日本語 div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
한국어 div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Nederlands div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Polski div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Português div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Română div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Русский div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
svenska div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
தமிழ் div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
తెలుగు div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
ภาษาไทย div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Tagalog div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Türkçe div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Українською div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Tiếng Việt div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
中文 div.-Dahb > ul._3PydS > li.yu122 > a.FXHbm
Cookie Policy div#onetrust-group-container > div#onetrust-policy > div#onetrust-policy-text > a
REJECT ALL div.ot-sdk-row > div#onetrust-button-group-parent > div#onetrust-button-group > button#onetrust-reject-all-handler
ACCEPT COOKIES div.ot-sdk-row > div#onetrust-button-group-parent > div#onetrust-button-group > button#onetrust-accept-btn-handler

These are opportunities to improve the legibility of your content.

Names and labels

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI
ul._399s9 > li > a._1nZQi > img._1RsYI ul._399s9 > li > a._1nZQi > img._1RsYI

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.

Best practices

Disabling zooming is problematic for users with low vision who rely on screen magnification to properly see the contents of a web page. Learn more about the viewport meta tag.

Why this matters

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

Source: MDN Permissions-Policy

Failing Elements
head > meta head > meta

These items highlight common accessibility best practices.

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Cookie Policy div#onetrust-group-container > div#onetrust-policy > div#onetrust-policy-text > a
○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
●ARIA attributes are used as specified for the element's role
●Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
●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.
●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
●Identical links have the same purpose.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○`[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
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○Skip links are focusable.
○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.
○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.
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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
Unload event listeners are deprecated and will be removed.
d35aaqx5ub95lt.cloudfront.net/js/app-6c532e98.js line 1, col 321625

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
zombie.duolingo.com/0/web.json?user=0&ts=1776295649&tzoffset=0
Failed to load resource: the server responded with a status of 404 ()
www.duolingo.com/users/undefined/streak-goal-current?_=1776295650037
Failed to load resource: the server responded with a status of 404 ()
www.duolingo.com/users/undefined/streak-goal-next-options?_=1776295650038
Failed to load resource: the server responded with a status of 404 ()
zombie.duolingo.com/0/web.json?user=0&ts=1776295690&tzoffset=0
Failed to load resource: the server responded with a status of 404 ()
●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 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
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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

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
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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 have descriptive text
●Links are crawlable
●robots.txt is valid
●Document has a valid `hreflang`
●Document has a valid `rel=canonical`

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