B — https://www.python.org | BeaverCheck Audit

Site Health

Score: 81 / 100

Based on 8 categories, 0 sections

How is this calculated?

The overall score is a weighted average of individual category scores. Categories with more impact on user experience and security carry more weight.

Performance 25%Security 25%Accessibility 15%SEO 10%Infrastructure 10%Compliance 8%Content 5%Sustainability 2%

Weights reflect general web best practices. Individual needs may differ.

Top Priorities (5)

Content-Security-Policy header is missing

Security › Security Headers

No Content-Security-Policy header found

Security › Content Security Policy

No <main> landmark found

Accessibility › Landmark Structure

Cross-Origin-Embedder-Policy header is missing

Security › Security Headers

Cross-Origin-Opener-Policy header is missing

Security › Security Headers

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Lighthouse Scores

Industry-standard audits powered by Google Lighthouse.

Performance

Accessibility

Best Practices

SEO

Core Web Vitals

Key metrics that affect user experience.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

2.89 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

3.90 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

48 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.003

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

2.89 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

4.13 s

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.

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

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

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

Request	Cache TTL	Transfer Size
www.python.org/static/stylesheets/style.c4f369bed0d3.css	604800.0 s	122.7 KiB
media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js	3600.0 s	8.7 KiB
www.python.org/static/fonts/FluxRegular.f5549a4fe75f.woff	604800.0 s	29.6 KiB
www.python.org/static/fonts/FluxBold.3fd71a747d5c.woff	604800.0 s	28.6 KiB
www.python.org/static/fonts/SourceSansPro-It-webfont.1aa29ac0f190.woff	604800.0 s	27.5 KiB
www.python.org/static/fonts/SourceSansPro-Regular-webfont.fd0d51605201.woff	604800.0 s	26.0 KiB
www.python.org/static/fonts/SourceSansPro-Bold-webfont.be855452e565.woff	604800.0 s	25.8 KiB
www.python.org/static/stylesheets/mq.a4feecea96fa.css	604800.0 s	17.4 KiB
www.python.org/static/img/python-logo.png	604800.0 s	15.7 KiB
www.python.org/static/js/main-min.e1f3949ae225.js	604800.0 s	9.9 KiB
www.python.org/static/js/libs/masonry.pkgd.min.js	604800.0 s	8.0 KiB
www.python.org/static/stylesheets/font-awesome.bf0c425cdb73.css	604800.0 s	7.1 KiB
www.python.org/static/js/libs/modernizr.js	604800.0 s	5.1 KiB
www.python.org/static/js/libs/html-includes.js	604800.0 s	294 B

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.

headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]

items: [map[reflowTime:45.482 source:map[type:text value:[unattributed]]]]

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

	URL	Resource Size	Est Savings
python™ `div.container > div.site-headline > a > img.python-logo`	www.python.org/static/img/python-logo.png	15.4 KiB	8.8 KiB

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.

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.

URL	Transfer Size	Duration
ajax.googleapis.com/ajax/libs/jqueryui/1.12.1/themes/smoothness/jquery-ui.css	8.8 KiB	762 ms
www.python.org/static/stylesheets/style.c4f369bed0d3.css	122.7 KiB	1.2 s
www.python.org/static/stylesheets/mq.a4feecea96fa.css	17.4 KiB
www.python.org/static/js/libs/modernizr.js	5.1 KiB
www.python.org/static/stylesheets/font-awesome.bf0c425cdb73.css	7.1 KiB	150 ms

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.

URL	Est Savings
www.python.org/static/fonts/SourceSansPro-It-webfont.1aa29ac0f190.woff	10 ms
www.python.org/static/fonts/FluxBold.3fd71a747d5c.woff	10 ms
www.python.org/static/fonts/SourceSansPro-Regular-webfont.fd0d51605201.woff	5.0 ms
www.python.org/static/fonts/SourceSansPro-Bold-webfont.be855452e565.woff	5.0 ms
www.python.org/static/fonts/FluxRegular.f5549a4fe75f.woff	5.0 ms

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

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.

TTI

Diagnostics

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

Estimated savings: 300 ms 24.0 KiB

URL	Transfer Size	Est Savings
www.python.org/static/stylesheets/style.c4f369bed0d3.css	122.7 KiB	16.3 KiB
www.python.org/static/stylesheets/mq.a4feecea96fa.css	17.4 KiB	7.8 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.

Estimated savings: 750 ms 128.4 KiB

URL	Transfer Size	Est Savings
www.python.org/static/stylesheets/style.c4f369bed0d3.css	122.5 KiB	111.4 KiB
www.python.org/static/stylesheets/mq.a4feecea96fa.css	17.2 KiB	17.0 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.

Estimated savings: 450 ms 59.2 KiB

URL	Transfer Size	Est Savings
ajax.googleapis.com/ajax/libs/jqueryui/1.12.1/jquery-ui.min.js	66.4 KiB	59.2 KiB

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

Estimated savings: 0.0 ms 2.2 KiB

URL	Transfer Size	Est Savings
www.python.org/static/js/main-min.e1f3949ae225.js	9.7 KiB	2.2 KiB

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

●Max Potential First Input Delay 80 ms

●Layout shift culprits

●Document request latency

●Optimize DOM size

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Avoids enormous network payloads Total size was 471 KiB

●JavaScript execution time 0.3 s

●Minimizes main-thread work 1.0 s

●Avoid long main-thread tasks 4 long tasks found

●Image elements have explicit `width` and `height`

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 110 ms

●Server Backend Latencies 90 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 0 ms

●Avoid large layout shifts 1 layout shift found

○INP breakdown

○LCP request discovery

○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.

ARIA

Some ARIA parent roles must contain specific child roles to perform their intended accessibility functions. Learn more about roles and required children elements.

Failing Elements
Python PSF Docs PyPI Jobs Community `div#touchnav-wrapper > div#top > nav.meta-navigation > ul.menu`
About Applications Quotes Getting Started Help Python Brochure Downloads All re… `footer#site-map > div.main-footer-links > div.container > ul#container`
Help & Contact Diversity Submit Website Bug Status `footer#site-map > div.site-base > div.container > ul.footer-links`

Some ARIA child roles must be contained by specific parent roles to properly perform their intended accessibility functions. Learn more about ARIA roles and required parent element.

Failing Elements
Applications `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Quotes `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Getting Started `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Help `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Brochure `ul#container > li.tier-1 > ul.subnav > li.tier-2`
All releases `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Source code `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Windows `ul#container > li.tier-1 > ul.subnav > li.tier-2`
macOS `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Android `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Other Platforms `ul#container > li.tier-1 > ul.subnav > li.tier-2`
License `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Alternative Implementations `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Docs `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Audio/Visual Talks `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Beginner's Guide `ul#container > li.tier-1 > ul.subnav > li.tier-2`
FAQ `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Non-English Docs `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PEP Index `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Books `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Essays `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Diversity `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Mailing Lists `ul#container > li.tier-1 > ul.subnav > li.tier-2`
IRC `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Forums `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PSF Annual Impact Report `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Conferences `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Special Interest Groups `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Logo `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Wiki `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Code of Conduct `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Community Awards `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Get Involved `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Shared Stories `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Arts `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Business `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Education `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Engineering `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Government `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Scientific `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Software Development `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python News `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PSF Newsletter `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PSF News `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PyCon US News `ul#container > li.tier-1 > ul.subnav > li.tier-2`
News from the Community `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Events `ul#container > li.tier-1 > ul.subnav > li.tier-2`
User Group Events `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Events Archive `ul#container > li.tier-1 > ul.subnav > li.tier-2`
User Group Events Archive `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Submit an Event `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Developer's Guide `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Issue Tracker `ul#container > li.tier-1 > ul.subnav > li.tier-2`
python-dev list `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Core Mentorship `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Report a Security Issue `ul#container > li.tier-1 > ul.subnav > li.tier-2`

Focusable descendents within an `[aria-hidden="true"]` element prevent those interactive elements from being available to users of assistive technologies like screen readers. Learn how `aria-hidden` affects focusable elements.

Failing Elements
Close `div#touchnav-wrapper > div#top > nav.meta-navigation > a#close-python-network`
The Python Network `div#touchnav-wrapper > div#top > nav.meta-navigation > a#python-network`
A A `div.container > div.options-bar-container > div.options-bar > div.adjust-font-size`

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.

Failing Elements
Back to Top `footer#site-map > div.main-footer-links > div.container > a#back-to-top-1`
About `div.container > ul#container > li.tier-1 > a`
Downloads `div.container > ul#container > li.tier-1 > a`
Documentation `div.container > ul#container > li.tier-1 > a`
Community `div.container > ul#container > li.tier-1 > a`
Success Stories `div.container > ul#container > li.tier-1 > a`
News `div.container > ul#container > li.tier-1 > a`
Events `div.container > ul#container > li.tier-1 > a`
Contributing `div.container > ul#container > li.tier-1 > a`
Back to Top `footer#site-map > div.main-footer-links > div.container > a#back-to-top-2`

These are opportunities to improve the legibility of your content.

Tables and lists

Screen readers have a specific way of announcing lists. Ensuring proper list structure aids screen reader output. Learn more about proper list structure.

Failing Elements
Applications Quotes Getting Started Help Python Brochure `div.container > ul#container > li.tier-1 > ul.subnav`
All releases Source code Windows macOS Android Other Platforms License Alternat… `div.container > ul#container > li.tier-1 > ul.subnav`
Docs Audio/Visual Talks Beginner's Guide FAQ Non-English Docs PEP Index Python … `div.container > ul#container > li.tier-1 > ul.subnav`
Diversity Mailing Lists IRC Forums PSF Annual Impact Report Python Conferences … `div.container > ul#container > li.tier-1 > ul.subnav`
Arts Business Education Engineering Government Scientific Software Development `div.container > ul#container > li.tier-1 > ul.subnav`
Python News PSF Newsletter PSF News PyCon US News News from the Community `div.container > ul#container > li.tier-1 > ul.subnav`
Python Events User Group Events Python Events Archive User Group Events Archive… `div.container > ul#container > li.tier-1 > ul.subnav`
Developer's Guide Issue Tracker python-dev list Core Mentorship Report a Securi… `div.container > ul#container > li.tier-1 > ul.subnav`

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.

Failing Elements
Python `div#top > nav.meta-navigation > ul.menu > li.python-meta`
PSF `div#top > nav.meta-navigation > ul.menu > li.psf-meta`
Docs `div#top > nav.meta-navigation > ul.menu > li.docs-meta`
PyPI `div#top > nav.meta-navigation > ul.menu > li.pypi-meta`
Jobs `div#top > nav.meta-navigation > ul.menu > li.jobs-meta`
Community `div#top > nav.meta-navigation > ul.menu > li.shop-meta`
About Applications Quotes Getting Started Help Python Brochure `div.main-footer-links > div.container > ul#container > li.tier-1`
Downloads All releases Source code Windows macOS Android Other Platforms Licens… `div.main-footer-links > div.container > ul#container > li.tier-1`
Documentation Docs Audio/Visual Talks Beginner's Guide FAQ Non-English Docs PEP… `div.main-footer-links > div.container > ul#container > li.tier-1`
Community Diversity Mailing Lists IRC Forums PSF Annual Impact Report Python Co… `div.main-footer-links > div.container > ul#container > li.tier-1`
Success Stories Arts Business Education Engineering Government Scientific Softw… `div.main-footer-links > div.container > ul#container > li.tier-1`
News Python News PSF Newsletter PSF News PyCon US News News from the Community `div.main-footer-links > div.container > ul#container > li.tier-1`
Events Python Events User Group Events Python Events Archive User Group Events … `div.main-footer-links > div.container > ul#container > li.tier-1`
Contributing Developer's Guide Issue Tracker python-dev list Core Mentorship Re… `div.main-footer-links > div.container > ul#container > li.tier-1`
Help & Contact `div.site-base > div.container > ul.footer-links > li.tier-1`
Diversity `div.site-base > div.container > ul.footer-links > li.tier-1`
Submit Website Bug `div.site-base > div.container > ul.footer-links > li.tier-1`
Status `div.site-base > div.container > ul.footer-links > li.tier-1`

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

Navigation

A value greater than 0 implies an explicit navigation ordering. Although technically valid, this often creates frustrating experiences for users who rely on assistive technologies. Learn more about the `tabindex` attribute.

Failing Elements
div.options-bar > form.search-the-site > fieldset > input#id-search-field `div.options-bar > form.search-the-site > fieldset > input#id-search-field`

These are opportunities to improve keyboard navigation in your application.

○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

●Image elements have `[alt]` attributes

●Form elements have associated labels

●`[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

●Elements use only permitted ARIA attributes

●ARIA `treeitem` elements have accessible names

●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

●Touch targets have sufficient size and spacing.

●Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.

●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

○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 the `role=text` attribute do not have focusable descendents.

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○Buttons have an accessible name

○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">`

○`<object>` elements have alternate text

○Select elements have associated label elements.

○Skip links are focusable.

○`<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.

○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.

Best Practices

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

Source	Description
media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js	`Error: No ad placements found. at w (https://media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js:1:11867) at https://media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js:1:12977`

●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 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

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.

Link destination	Link Text
www.python.org/doc/	Learn More
blog.python.org/	More
www.python.org/events/calendars/	More
www.python.org/success-stories/	More
www.python.org/about/apps	More
www.python.org/psf/	Learn 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

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

○Document has a valid `rel=canonical`

Lighthouse Scores

Industry-standard audits powered by Google Lighthouse. — Desktop

Performance

Accessibility

Best Practices

SEO

Core Web Vitals

Key metrics that affect user experience. — Desktop

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

614 ms

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

936 ms

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

0 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.258

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

640 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

936 ms

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.

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

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

Request	Cache TTL	Transfer Size
www.python.org/static/stylesheets/style.c4f369bed0d3.css	604800.0 s	122.7 KiB
media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js	3600.0 s	8.7 KiB
www.python.org/static/fonts/FluxRegular.f5549a4fe75f.woff	604800.0 s	29.5 KiB
www.python.org/static/fonts/FluxBold.3fd71a747d5c.woff	604800.0 s	28.6 KiB
www.python.org/static/fonts/SourceSansPro-It-webfont.1aa29ac0f190.woff	604800.0 s	27.5 KiB
www.python.org/static/fonts/SourceSansPro-Regular-webfont.fd0d51605201.woff	604800.0 s	26.0 KiB
www.python.org/static/fonts/SourceSansPro-Bold-webfont.be855452e565.woff	604800.0 s	25.8 KiB
www.python.org/static/stylesheets/mq.a4feecea96fa.css	604800.0 s	17.3 KiB
www.python.org/static/img/python-logo.png	604800.0 s	15.6 KiB
www.python.org/static/img/python-logo-large.c36dccadd999.png?1694722768	604800.0 s	12.9 KiB
www.python.org/static/js/main-min.e1f3949ae225.js	604800.0 s	9.9 KiB
www.python.org/static/js/libs/masonry.pkgd.min.js	604800.0 s	8.0 KiB
www.python.org/static/stylesheets/font-awesome.bf0c425cdb73.css	604800.0 s	7.2 KiB
www.python.org/static/js/libs/modernizr.js	604800.0 s	5.1 KiB
www.python.org/static/js/libs/html-includes.js	604800.0 s	317 B

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.

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:0.257904] map[node:map[boundingRect:map[bottom:969 height:237 left:99 right:1251 top:732 width:1152] lhId:page-2-DIV nodeLabel:Get Started Whether you're new to programming or an experienced developer, it'… path:1,HTML,1,BODY,0,DIV,5,DIV,1,DIV,0,SECTION,1,DIV selector:div#content > div.container > section.main-content > div.row snippet:<div class="row"> type:node] score:0.149392 subItems:map[items:[map[cause:Web font extra:map[type:url value:https://www.python.org/static/fonts/SourceSansPro-Regular-webfont.fd0d51605201.woff]] map[cause:Web font extra:map[type:url value:https://www.python.org/static/fonts/FluxRegular.f5549a4fe75f.woff]] map[cause:Web font extra:map[type:url value:https://www.python.org/static/fonts/SourceSansPro-Bold-webfont.be855452e565.woff]] map[cause:Web font extra:map[type:url value:https://www.python.org/static/fonts/SourceSansPro-It-webfont.1aa29ac0f190.woff]] map[cause:Web font extra:map[type:url value:https://www.python.org/static/fonts/FluxBold.3fd71a747d5c.woff]]] type:subitems]] map[node:map[boundingRect:map[bottom:1923 height:1315 left:0 right:1350 top:609 width:1350] lhId:page-7-DIV nodeLabel: Join us in Long Beach, CA starting May 13, 2026. Grab your ticket and discount… path:1,HTML,1,BODY,0,DIV,5,DIV selector:body#homepage > div#touchnav-wrapper > div#content snippet:<div id="content" class="content-wrapper"> type:node] score:0.108512]]

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:12.911 source:map[column:9771 line:2 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.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:43.865 source:map[type:text value:[unattributed]]] map[reflowTime:0.564 source:map[column:21651 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:0.295 source:map[column:21748 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:0.186 source:map[column:21978 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:0.152 source:map[column:22405 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:0.211 source:map[column:22560 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:0.206 source:map[column:22705 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:0.689 source:map[column:6429 line:8 type:source-location url:https://www.python.org/static/js/libs/masonry.pkgd.min.js urlProvider:network]] map[reflowTime:0.433 source:map[column:6586 line:8 type:source-location url:https://www.python.org/static/js/libs/masonry.pkgd.min.js urlProvider:network]] map[reflowTime:0.274 source:map[column:6624 line:8 type:source-location url:https://www.python.org/static/js/libs/masonry.pkgd.min.js urlProvider:network]] map[reflowTime:3.913 source:map[column:75860 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:3.47 source:map[column:3477 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:1.63 source:map[column:3463 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:0.888 source:map[column:75206 line:1 type:source-location url:https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js urlProvider:network]] map[reflowTime:0.228 source:map[column:787 line:0 type:source-location url:https://analytics.python.org/js/script.file-downloads.outbound-links.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

	URL	Resource Size	Est Savings
python™ `div.container > div.site-headline > a > img.python-logo`	www.python.org/static/img/python-logo.png	15.4 KiB	11.6 KiB

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.

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.

URL	Transfer Size	Duration
ajax.googleapis.com/ajax/libs/jqueryui/1.12.1/themes/smoothness/jquery-ui.css	8.8 KiB	209 ms
www.python.org/static/stylesheets/style.c4f369bed0d3.css	122.7 KiB	240 ms
www.python.org/static/stylesheets/mq.a4feecea96fa.css	17.3 KiB
www.python.org/static/js/libs/modernizr.js	5.1 KiB
www.python.org/static/stylesheets/font-awesome.bf0c425cdb73.css	7.2 KiB

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.

URL	Est Savings
www.python.org/static/fonts/SourceSansPro-Regular-webfont.fd0d51605201.woff	10 ms
www.python.org/static/fonts/SourceSansPro-Bold-webfont.be855452e565.woff	10 ms
www.python.org/static/fonts/SourceSansPro-It-webfont.1aa29ac0f190.woff	10 ms
www.python.org/static/fonts/FluxBold.3fd71a747d5c.woff	10 ms
www.python.org/static/fonts/FluxRegular.f5549a4fe75f.woff	5.0 ms

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

Diagnostics

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

Estimated savings: 40 ms 24.0 KiB

URL	Transfer Size	Est Savings
www.python.org/static/stylesheets/style.c4f369bed0d3.css	122.7 KiB	16.3 KiB
www.python.org/static/stylesheets/mq.a4feecea96fa.css	17.3 KiB	7.7 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.

Estimated savings: 80 ms 125.5 KiB

URL	Transfer Size	Est Savings
www.python.org/static/stylesheets/style.c4f369bed0d3.css	122.5 KiB	111.3 KiB
www.python.org/static/stylesheets/mq.a4feecea96fa.css	17.2 KiB	14.3 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.

Estimated savings: 40 ms 59.2 KiB

URL	Transfer Size	Est Savings
ajax.googleapis.com/ajax/libs/jqueryui/1.12.1/jquery-ui.min.js	66.4 KiB	59.2 KiB

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

Estimated savings: 0.0 ms 2.2 KiB

URL	Transfer Size	Est Savings
www.python.org/static/js/main-min.e1f3949ae225.js	9.7 KiB	2.2 KiB

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

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

Element	Layout shift score
Get Started Whether you're new to programming or an experienced developer, it'… `div#content > div.container > section.main-content > div.row`	0.149
Join us in Long Beach, CA starting May 13, 2026. Grab your ticket and discount… `body#homepage > div#touchnav-wrapper > div#content`	0.109

●Document request latency

●Optimize DOM size

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Time to Interactive 0.9 s

●Max Potential First Input Delay 30 ms

●Avoids enormous network payloads Total size was 487 KiB

●JavaScript execution time 0.1 s

●Minimizes main-thread work 0.4 s

●Image elements have explicit `width` and `height`

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 110 ms

●Server Backend Latencies 280 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 0 ms

○INP breakdown

○LCP request discovery

○User Timing marks and measures

○Avoid long main-thread tasks

○Avoid non-composited animations

Accessibility

ARIA

Some ARIA parent roles must contain specific child roles to perform their intended accessibility functions. Learn more about roles and required children elements.

Failing Elements
Python PSF Docs PyPI Jobs Community `div#touchnav-wrapper > div#top > nav.meta-navigation > ul.menu`
About Downloads Documentation Community Success Stories News Events `header.main-header > div.container > nav#mainnav > ul.navigation`
About Applications Quotes Getting Started Help Python Brochure Downloads All re… `footer#site-map > div.main-footer-links > div.container > ul#container`
Help & General Contact Diversity Initiatives Submit Website Bug Status `footer#site-map > div.site-base > div.container > ul.footer-links`

Some ARIA child roles must be contained by specific parent roles to properly perform their intended accessibility functions. Learn more about ARIA roles and required parent element.

Failing Elements
Applications `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Quotes `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Getting Started `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Help `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Brochure `ul#container > li.tier-1 > ul.subnav > li.tier-2`
All releases `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Source code `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Windows `ul#container > li.tier-1 > ul.subnav > li.tier-2`
macOS `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Android `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Other Platforms `ul#container > li.tier-1 > ul.subnav > li.tier-2`
License `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Alternative Implementations `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Docs `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Audio/Visual Talks `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Beginner's Guide `ul#container > li.tier-1 > ul.subnav > li.tier-2`
FAQ `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Non-English Docs `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PEP Index `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Books `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Essays `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Diversity `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Mailing Lists `ul#container > li.tier-1 > ul.subnav > li.tier-2`
IRC `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Forums `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PSF Annual Impact Report `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Conferences `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Special Interest Groups `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Logo `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Wiki `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Code of Conduct `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Community Awards `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Get Involved `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Shared Stories `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Arts `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Business `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Education `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Engineering `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Government `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Scientific `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Software Development `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python News `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PSF Newsletter `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PSF News `ul#container > li.tier-1 > ul.subnav > li.tier-2`
PyCon US News `ul#container > li.tier-1 > ul.subnav > li.tier-2`
News from the Community `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Events `ul#container > li.tier-1 > ul.subnav > li.tier-2`
User Group Events `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Python Events Archive `ul#container > li.tier-1 > ul.subnav > li.tier-2`
User Group Events Archive `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Submit an Event `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Developer's Guide `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Issue Tracker `ul#container > li.tier-1 > ul.subnav > li.tier-2`
python-dev list `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Core Mentorship `ul#container > li.tier-1 > ul.subnav > li.tier-2`
Report a Security Issue `ul#container > li.tier-1 > ul.subnav > li.tier-2`

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.

Failing Elements
div.options-bar > form.search-the-site > fieldset > input#id-search-field `div.options-bar > form.search-the-site > fieldset > input#id-search-field`
# Python 3: Fibonacci series up to n >>> def fib(n): >>> a, b = 0, 1 >>> … `li.flex-active-slide > div.slide-code > pre > code`
# Python 3: Fibonacci series up to n `div.slide-code > pre > code > span.comment`
0 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987 `div.slide-code > pre > code > span.output`
About `div.container > ul#container > li.tier-1 > a`
Downloads `div.container > ul#container > li.tier-1 > a`
Documentation `div.container > ul#container > li.tier-1 > a`
Community `div.container > ul#container > li.tier-1 > a`
Success Stories `div.container > ul#container > li.tier-1 > a`
News `div.container > ul#container > li.tier-1 > a`
Events `div.container > ul#container > li.tier-1 > a`
Contributing `div.container > ul#container > li.tier-1 > a`

These are opportunities to improve the legibility of your content.

Tables and lists

Screen readers have a specific way of announcing lists. Ensuring proper list structure aids screen reader output. Learn more about proper list structure.

Failing Elements
Applications Quotes Getting Started Help Python Brochure `div.container > ul#container > li.tier-1 > ul.subnav`
All releases Source code Windows macOS Android Other Platforms License Alternat… `div.container > ul#container > li.tier-1 > ul.subnav`
Docs Audio/Visual Talks Beginner's Guide FAQ Non-English Docs PEP Index Python … `div.container > ul#container > li.tier-1 > ul.subnav`
Diversity Mailing Lists IRC Forums PSF Annual Impact Report Python Conferences … `div.container > ul#container > li.tier-1 > ul.subnav`
Arts Business Education Engineering Government Scientific Software Development `div.container > ul#container > li.tier-1 > ul.subnav`
Python News PSF Newsletter PSF News PyCon US News News from the Community `div.container > ul#container > li.tier-1 > ul.subnav`
Python Events User Group Events Python Events Archive User Group Events Archive… `div.container > ul#container > li.tier-1 > ul.subnav`
Developer's Guide Issue Tracker python-dev list Core Mentorship Report a Securi… `div.container > ul#container > li.tier-1 > ul.subnav`

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.

Failing Elements
Python `div#top > nav.meta-navigation > ul.menu > li.python-meta`
PSF `div#top > nav.meta-navigation > ul.menu > li.psf-meta`
Docs `div#top > nav.meta-navigation > ul.menu > li.docs-meta`
PyPI `div#top > nav.meta-navigation > ul.menu > li.pypi-meta`
Jobs `div#top > nav.meta-navigation > ul.menu > li.jobs-meta`
Community `div#top > nav.meta-navigation > ul.menu > li.shop-meta`
About `div.container > nav#mainnav > ul.navigation > li#about`
Downloads `div.container > nav#mainnav > ul.navigation > li#downloads`
Documentation `div.container > nav#mainnav > ul.navigation > li#documentation`
Community `div.container > nav#mainnav > ul.navigation > li#community`
Success Stories `div.container > nav#mainnav > ul.navigation > li#success-stories`
News `div.container > nav#mainnav > ul.navigation > li#news`
Events `div.container > nav#mainnav > ul.navigation > li#events`
About Applications Quotes Getting Started Help Python Brochure `div.main-footer-links > div.container > ul#container > li.tier-1`
Downloads All releases Source code Windows macOS Android Other Platforms Licens… `div.main-footer-links > div.container > ul#container > li.tier-1`
Documentation Docs Audio/Visual Talks Beginner's Guide FAQ Non-English Docs PEP… `div.main-footer-links > div.container > ul#container > li.tier-1`
Community Diversity Mailing Lists IRC Forums PSF Annual Impact Report Python Co… `div.main-footer-links > div.container > ul#container > li.tier-1`
Success Stories Arts Business Education Engineering Government Scientific Softw… `div.main-footer-links > div.container > ul#container > li.tier-1`
News Python News PSF Newsletter PSF News PyCon US News News from the Community `div.main-footer-links > div.container > ul#container > li.tier-1`
Events Python Events User Group Events Python Events Archive User Group Events … `div.main-footer-links > div.container > ul#container > li.tier-1`
Contributing Developer's Guide Issue Tracker python-dev list Core Mentorship Re… `div.main-footer-links > div.container > ul#container > li.tier-1`
Help & General Contact `div.site-base > div.container > ul.footer-links > li.tier-1`
Diversity Initiatives `div.site-base > div.container > ul.footer-links > li.tier-1`
Submit Website Bug `div.site-base > div.container > ul.footer-links > li.tier-1`
Status `div.site-base > div.container > ul.footer-links > li.tier-1`

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

Navigation

Failing Elements
div.options-bar > form.search-the-site > fieldset > input#id-search-field `div.options-bar > form.search-the-site > fieldset > input#id-search-field`
GO `div.options-bar > form.search-the-site > fieldset > button#submit`

These are opportunities to improve keyboard navigation in your application.

○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

●Form elements have associated labels

●`[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

●ARIA `treeitem` elements have accessible names

●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

●Touch targets have sufficient size and spacing.

●Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.

●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

○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 the `role=text` attribute do not have focusable descendents.

○ARIA toggle fields have accessible names

○ARIA `tooltip` 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">`

○`<object>` elements have alternate text

○Select elements have associated label elements.

○Skip links are focusable.

○`<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.

○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.

Best Practices

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

Source	Description
media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js	`Error: No ad placements found. at w (https://media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js:1:11867) at https://media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js:1:12977`

●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 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

SEO

Content Best Practices

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

Link destination	Link Text
www.python.org/doc/	Learn More
blog.python.org/	More
www.python.org/events/calendars/	More
www.python.org/success-stories/	More
www.python.org/about/apps	More
www.python.org/psf/	Learn 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

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

○Document has a valid `rel=canonical`

Results for https://www.python.org

Site Health

Top Priorities (5)

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

ARIA

Contrast

Tables and lists

Navigation

Best Practices

General

SEO

Content Best Practices

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

ARIA

Contrast

Tables and lists

Navigation

Best Practices

General

SEO

Content Best Practices

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