C — https://reactnative.dev | BeaverCheck Audit

Site Health

Score: 74 / 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

2 image-only link(s) without alt text

Accessibility › Link & Button Quality

No <main> landmark found

Accessibility › Landmark Structure

Cross-Origin-Embedder-Policy header is missing

Security › Security Headers

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[![BeaverCheck](https://beavercheck.com/badge?url=https%3A%2F%2Freactnative.dev)](https://beavercheck.com/results/b6fda8ce-3f66-45ed-ac6e-e652bc65e74b)

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Lighthouse Scores

Industry-standard audits powered by Google Lighthouse.

Performance

Accessibility

Best Practices

100

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.

2.03 s

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

6.70 s

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

893 ms

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

0.147

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

2.39 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.

9.84 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.

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:0.147146] map[node:map[boundingRect:map[bottom:9512 height:9391 left:0 right:412 top:121 width:412] lhId:page-1-DIV nodeLabel:React Native Learn once, write anywhere. Get Started Learn the Basics Create na… path:1,HTML,1,BODY,2,DIV,44,DIV selector:body.navigation-with-keyboard > div#__docusaurus > div#__docusaurus_skipToContent_fallback snippet:<div id="__docusaurus_skipToContent_fallback" class="theme-layout-main main-wrapper mainWrapper_MB5r homepage"> type:node] score:0.146117] map[node:map[boundingRect:map[bottom:0 height:0 left:0 right:0 top:0 width:0] lhId:page-3-A nodeLabel:Follow @reactnative path: selector:a.twitter-follow-button snippet:<a class="twitter-follow-button" href="https://twitter.com/reactnative?ref_src=twsrc%5Etfw" data-show-count="false" data-size="large" data-twitter-extracted-i1775328134472175272="true"> type:node] score:0.001029]]

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
/assets/fonts/Source-Code-Pro-Regular-a7968a8070a7b4cfb40...	135 ms
/assets/fonts/Optimistic-Display-Regular-b0e4e99f91efd002...	125 ms
/assets/fonts/Optimistic-Display-Bold-cac0444e353f65c7263...	125 ms
/assets/fonts/Optimistic-Display-Light-199be98cf48e5b4c68...	125 ms
/assets/fonts/Optimistic-Display-Medium-0670086c0b69b5069...	125 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.

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

items: [map[reflowTime:52.888 source:map[type:text value:[unattributed]]]]

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.

More than 4 preconnect connections were found. These should be used sparingly and only to the most important origins.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.

title: Preconnected origins

description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.

title: Preconnect candidates

value: No additional origins are good candidates for preconnecting

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

URL	Transfer Size	Duration
reactnative.dev/assets/css/styles.5393e7c0.css	31.7 KiB	300 ms

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

Request	Cache TTL	Transfer Size
img.youtube.com/vi/NiYwlvXsBKw/maxresdefault.jpg	7200.0 s	131.1 KiB
img.youtube.com/vi/wUDeLT6WXnQ/maxresdefault.jpg	7200.0 s	75.6 KiB
img.youtube.com/vi/Q5SMmKb7qVI/maxresdefault.jpg	7200.0 s	52.8 KiB
img.youtube.com/vi/NCAY0HIfrwc/maxresdefault.jpg	7200.0 s	44.2 KiB
platform.twitter.com/widgets.js	1800.0 s	27.3 KiB
/collect/website/js/tRaiETqnLgj758hTBazgd8ryO5qrZo8Exadq9...	0.0 ms	15.7 KiB
snack.expo.dev/embed.js	0.0 ms	1.6 KiB
widget.surveymonkey.com/collect/website/js/cookie.js?_=1775328134155	0.0 ms	326 B

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
A React Native UI pointing out native elements like Views, ScrollViews, and more `div#__docusaurus_skipToContent_fallback > div.wrapper_Wq0p > div.container_M3fB > img.flyoutIllustration_r9BI`	reactnative.dev/img/homepage/dissection.png	286.8 KiB	230.4 KiB
List of developer tool toggles for debugging, performance, and more `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/tools.png	130.8 KiB	109.7 KiB
React Conf 2025 React Native Keynote `div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3 > img.video_v06Q`	img.youtube.com/vi/NiYwlvXsBKw/maxresdefault.jpg	131.0 KiB	102.5 KiB
File system with folders and files representing screens and navigation `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/file-based-routing.png	89.6 KiB	68.5 KiB
Explain Like I'm 5: React Native `div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3 > img.video_v06Q`	img.youtube.com/vi/wUDeLT6WXnQ/maxresdefault.jpg	75.1 KiB	58.8 KiB
Grid of icons representing libraries, SDKs, and native code `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/libraries.png	78.2 KiB	57.1 KiB
React Conf 2024 React Native Keynote `div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3 > img.video_v06Q`	img.youtube.com/vi/Q5SMmKb7qVI/maxresdefault.jpg	52.7 KiB	41.2 KiB
Android device and iOS device `div.platformsContainer_LdgS > div.featureContainer_vkjP > div.deviceContainer_D11o > img.devices_CEHn`	reactnative.dev/img/homepage/devices.png	69.3 KiB	38.5 KiB
Mobile Innovation with React Native, ComponentKit, and Litho `div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3 > img.video_v06Q`	img.youtube.com/vi/NCAY0HIfrwc/maxresdefault.jpg	44.1 KiB	34.5 KiB

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

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
React Native Learn once, write anywhere. Get Started Learn the Basics Create na… `body.navigation-with-keyboard > div#__docusaurus > div#__docusaurus_skipToContent_fallback`	0.146
Follow @reactnative `a.twitter-follow-button`	0.001

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.

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

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: 150 ms 155.4 KiB

URL	Transfer Size	Est Savings
www.googletagmanager.com/gtag/js?id=G-58L13S6BDP	141.9 KiB	62.1 KiB
ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.js	82.4 KiB	50.7 KiB
reactnative.dev/assets/js/main.f6a6aa6b.js	223.3 KiB	42.5 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.

URL	Total CPU Time	Script Evaluation	Script Parse
reactnative.dev/assets/js/main.f6a6aa6b.js	1.3 s	968 ms	173 ms
reactnative.dev/	1.0 s	84 ms	8.6 ms
Unattributable	736 ms	13 ms	0.0 ms
www.googletagmanager.com/gtag/js?id=G-58L13S6BDP	373 ms	268 ms	101 ms
platform.twitter.com/widgets.js	277 ms	227 ms	14 ms
ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.js	136 ms	67 ms	57 ms
reactnative.dev/assets/js/1df93b7f.a1a1db4e.js	53 ms	1.5 ms	51 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

Category	Time Spent
Script Evaluation	1.7 s
Other	902 ms
Style & Layout	773 ms
Script Parsing & Compilation	428 ms
Rendering	94 ms
Parse HTML & CSS	82 ms
Garbage Collection	35 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

Failure reason	Failure type
The page has an unload handler in a sub frame.	Actionable

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

Estimated savings: 0.0 ms 42.9 KiB

URL	Transfer Size	Est Savings
ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.js	82.4 KiB	39.3 KiB
/collect/website/js/tRaiETqnLgj758hTBazgd8ryO5qrZo8Exadq9...	15.4 KiB	3.6 KiB

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

URL	Transfer Size
reactnative.dev/img/homepage/dissection.png	287.0 KiB
reactnative.dev/img/homepage/dissection-dark.png	277.8 KiB
reactnative.dev/assets/js/main.f6a6aa6b.js	243.4 KiB
reactnative.dev/	183.0 KiB
reactnative.dev/assets/js/1df93b7f.a1a1db4e.js	178.5 KiB
www.googletagmanager.com/gtag/js?id=G-58L13S6BDP	142.2 KiB
reactnative.dev/img/showcase/amazon-shopping.png	136.6 KiB
img.youtube.com/vi/NiYwlvXsBKw/maxresdefault.jpg	131.1 KiB
reactnative.dev/img/homepage/tools.png	130.9 KiB
/widgets/widget_iframe.2f70fb173b9000da126c79afe2098f02.h...	103.4 KiB

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

	URL
A React Native UI pointing out native elements like Views, ScrollViews, and more `div#__docusaurus_skipToContent_fallback > div.wrapper_Wq0p > div.container_M3fB > img.flyoutIllustration_r9BI`	reactnative.dev/img/homepage/dissection.png
Android device and iOS device `div.platformsContainer_LdgS > div.featureContainer_vkjP > div.deviceContainer_D11o > img.devices_CEHn`	reactnative.dev/img/homepage/devices.png
File system with folders and files representing screens and navigation `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/file-based-routing.png
Grid of icons representing libraries, SDKs, and native code `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/libraries.png
List of developer tool toggles for debugging, performance, and more `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/tools.png
Facebook `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/facebook.webp
Microsoft Office `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/officemobile.png
Microsoft Teams `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/teamsmobile.png
Xbox Game Pass `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/xboxgamepass.png
Shop: All your favorite brands `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/shop.webp
PUMA `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/puma.png
PlayStation App `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/playstation.png
WordPress - Website Builder `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/wordpress.png
Bolt Food: Delivery & Takeaway `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/bolt.png
Klarna \| Shop now. Pay later. `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/klarna.jpg
NFL `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/nfl.webp
Microsoft Outlook `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/outlookmobile.png
Amazon Shopping `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/amazon-shopping.png
Tableau `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/tableau.webp
Mattermost `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/mattermost.webp
Meta Horizon `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/metahorizon.webp
Shopify `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/shopify.png
Tesla `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/tesla.png
FlipKart `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/flipkart.png
Facebook Ads Manager `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/adsmanager.png
Coinbase `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/coinbase.png
Mercari `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/mercari.png
Bloomberg `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/bloomberg.png
Discord `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/discord.png
Meta Open Source Logo `div.footer__bottom > div.margin-bottom--sm > a.footerLogoLink_tutC > img.footer__logo`	reactnative.dev/img/oss_logo.svg
Messenger Desktop `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/messengerdesktop.png
div.theme-layout-navbar-left > a.navbar__brand > div.navbar__logo > img.themedComponent_siVc `div.theme-layout-navbar-left > a.navbar__brand > div.navbar__logo > img.themedComponent_siVc`	reactnative.dev/img/header_logo.svg
div.navbar-sidebar__brand > a.navbar__brand > div.navbar__logo > img.themedComponent_siVc `div.navbar-sidebar__brand > a.navbar__brand > div.navbar__logo > img.themedComponent_siVc`	reactnative.dev/img/header_logo.svg

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

●Document request latency

●Optimize DOM size

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Reduce unused CSS

●User Timing marks and measures 5 user timings

●Avoid long main-thread tasks 11 long tasks found

●Network Requests

●Network Round Trip Times 20 ms

●Server Backend Latencies 70 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 10 ms

○INP breakdown

○LCP request discovery

○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.

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.

Failing Elements
React Native brings the best parts of developing with React to native developme… `div.wrapper_Wq0p > div.container_M3fB > div.container_li6i > h3.description_wtc5`
React Native lets you create truly native apps and doesn't compromise your user… `div.wrapper_Wq0p > div.container_M3fB > div.container_li6i > h3.description_wtc5`
React Native brings the React programming paradigm to platforms like Android an… `div.wrapper_Wq0p > div.container_M3fB > div.container_li6i > h3.description_wtc5`
Watch talks by the React team and learn how to get the most out of React Native… `div.wrapper_Wq0p > div.container_M3fB > div.container_li6i > h3.description_wtc5`

These are opportunities to improve keyboard navigation in your application.

Best practices

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

Failing Elements
html.plugin-pages `html.plugin-pages`

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.

Failing Elements
Why React Native? 1:42 `div.wrapper_Wq0p > div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3`
React Conf 2025 React Native Keynote 55:13 `div.wrapper_Wq0p > div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3`
React Conf 2024 React Native Keynote 55:14 `div.wrapper_Wq0p > div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3`
FB 2019 Mobile innovation with React Native 45:29 `div.wrapper_Wq0p > div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3`

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` attributes match their roles

●`[aria-hidden="true"]` is not present on the document `<body>`

●`[role]`s have all required `[aria-*]` attributes

●`[role]` values are valid

●`[aria-*]` attributes have valid values

●`[aria-*]` attributes are valid and not misspelled

●Buttons have an accessible name

●Image elements have `[alt]` attributes

●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.

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

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

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

●Elements use only permitted ARIA attributes

●Background and foreground colors have a sufficient contrast ratio

●Document has a `<title>` element

●`<frame>` or `<iframe>` elements have a title

●`<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

●Touch targets have sufficient size and spacing.

●Deprecated ARIA roles were not used

●Identical links have the same purpose.

○`[accesskey]` values are unique

○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

○`<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.

○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.

○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.

Best Practices

User Experience

Image display dimensions should match natural aspect ratio. Learn more about image aspect ratio.

	URL	Aspect Ratio (Displayed)	Aspect Ratio (Actual)
File system with folders and files representing screens and navigation `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/file-based-routing.png	286 x 148 (1.93)	699 x 351 (1.99)
Grid of icons representing libraries, SDKs, and native code `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/libraries.png	286 x 148 (1.93)	699 x 350 (2.00)
List of developer tool toggles for debugging, performance, and more `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/tools.png	286 x 148 (1.93)	698 x 350 (1.99)

General

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

Deprecation / Warning	Source
Unload event listeners are deprecated and will be removed.	ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.js line 1071, col 10

Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. Learn more about source maps.

URL	Map URL
reactnative.dev/assets/js/main.f6a6aa6b.js
cdn.jsdelivr.net/npm/focus-visible@5.2.0/dist/focus-visible.min.js	cdn.jsdelivr.net/npm/focus-visible@5.2.0/dist/focus-visible.min.js.map

●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

●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 clickjacking with XFO or CSP

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

○Redirects HTTP traffic to HTTPS

100

SEO

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

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`

Lighthouse Scores

Industry-standard audits powered by Google Lighthouse. — Desktop

Performance

Accessibility

Best Practices

100

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.

604 ms

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

2.26 s

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

131 ms

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

0.108

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

712 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.

2.55 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.

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
img.youtube.com/vi/NiYwlvXsBKw/maxresdefault.jpg	7200.0 s	131.1 KiB
img.youtube.com/vi/wUDeLT6WXnQ/maxresdefault.jpg	7200.0 s	75.2 KiB
img.youtube.com/vi/Q5SMmKb7qVI/maxresdefault.jpg	7200.0 s	52.8 KiB
img.youtube.com/vi/NCAY0HIfrwc/maxresdefault.jpg	7200.0 s	44.5 KiB
platform.twitter.com/widgets.js	1800.0 s	27.3 KiB
/collect/website/js/tRaiETqnLgj758hTBazgd8ryO5qrZo8Exadq9...	0.0 ms	15.8 KiB
snack.expo.dev/embed.js	0.0 ms	1.6 KiB
widget.surveymonkey.com/collect/website/js/cookie.js?_=1775328151774	0.0 ms	407 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.

items: [map[node:map[type:text value:Total] score:0.107918] map[node:map[boundingRect:map[bottom:974 height:288 left:102 right:1209 top:686 width:1107] lhId:page-1-svg nodeLabel:div.container_b02U > div.backgroundContainer_Huei > div.devices_vH96 > svg.svgContent_v9JU path:1,HTML,1,BODY,2,DIV,44,DIV,0,DIV,1,DIV,1,DIV,0,svg selector:div.container_b02U > div.backgroundContainer_Huei > div.devices_vH96 > svg.svgContent_v9JU snippet:<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="1107" height="288" fill="none" class="svgContent_v9JU"> type:node] score:0.105069] map[node:map[boundingRect:map[bottom:112 height:47 left:490 right:1334 top:66 width:844] lhId:page-2-DIV nodeLabel:Development Contributing Community Showcase Blog Search path:1,HTML,1,BODY,2,DIV,43,NAV,0,DIV,1,DIV selector:div#__docusaurus > nav.theme-layout-navbar > div.navbar__inner > div.theme-layout-navbar-right snippet:<div class="theme-layout-navbar-right navbar__items navbar__items--right"> type:node] score:0.002681 subItems:map[items:[map[cause:Web font extra:map[type:url value:https://reactnative.dev/assets/fonts/Optimistic-Display-Light-199be98cf48e5b4c688356b08a02362c.woff2]] map[cause:Web font extra:map[type:url value:https://reactnative.dev/assets/fonts/Optimistic-Display-Bold-cac0444e353f65c7263980c51631096a.woff2]] map[cause:Web font extra:map[type:url value:https://reactnative.dev/assets/fonts/Optimistic-Display-Medium-0670086c0b69b506967af1cab0ed1f22.woff2]] map[cause:Web font extra:map[type:url value:https://reactnative.dev/assets/fonts/Optimistic-Display-Regular-b0e4e99f91efd0021c3ab8e4df0e6e1b.woff2]] map[cause:Web font extra:map[type:url value:https://reactnative.dev/assets/fonts/Source-Code-Pro-Regular-a7968a8070a7b4cfb4050a96e1eea6eb.woff2]]] type:subitems]] map[node:map[boundingRect:map[bottom:0 height:0 left:0 right:0 top:0 width:0] lhId:page-7-A nodeLabel:Follow @reactnative path: selector:a.twitter-follow-button snippet:<a class="twitter-follow-button" href="https://twitter.com/reactnative?ref_src=twsrc%5Etfw" data-show-count="false" data-size="large" data-twitter-extracted-i17753281523375822="true"> type:node] score:0.000168]]

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
/assets/fonts/Optimistic-Display-Light-199be98cf48e5b4c68...	170 ms
/assets/fonts/Optimistic-Display-Bold-cac0444e353f65c7263...	170 ms
/assets/fonts/Optimistic-Display-Medium-0670086c0b69b5069...	165 ms
/assets/fonts/Optimistic-Display-Regular-b0e4e99f91efd002...	165 ms
/assets/fonts/Source-Code-Pro-Regular-a7968a8070a7b4cfb40...	15 ms

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

items: [map[reflowTime:180.387 source:map[type:text value:[unattributed]]]]

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.

More than 4 preconnect connections were found. These should be used sparingly and only to the most important origins.

title: Preconnected origins

description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.

title: Preconnect candidates

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
A React Native UI pointing out native elements like Views, ScrollViews, and more `div#__docusaurus_skipToContent_fallback > div.wrapper_Wq0p > div.container_M3fB > img.flyoutIllustration_r9BI`	reactnative.dev/img/homepage/dissection.png	286.8 KiB	230.7 KiB
List of developer tool toggles for debugging, performance, and more `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/tools.png	130.8 KiB	123.3 KiB
React Conf 2025 React Native Keynote `div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3 > img.video_v06Q`	img.youtube.com/vi/NiYwlvXsBKw/maxresdefault.jpg	131.0 KiB	120.4 KiB
File system with folders and files representing screens and navigation `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/file-based-routing.png	89.6 KiB	82.1 KiB
Grid of icons representing libraries, SDKs, and native code `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/libraries.png	78.2 KiB	70.7 KiB
Explain Like I'm 5: React Native `div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3 > img.video_v06Q`	img.youtube.com/vi/wUDeLT6WXnQ/maxresdefault.jpg	75.1 KiB	69.1 KiB
Android device and iOS device `div.platformsContainer_LdgS > div.featureContainer_vkjP > div.deviceContainer_D11o > img.devices_CEHn`	reactnative.dev/img/homepage/devices.png	69.3 KiB	55.0 KiB
React Conf 2024 React Native Keynote `div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3 > img.video_v06Q`	img.youtube.com/vi/Q5SMmKb7qVI/maxresdefault.jpg	52.7 KiB	48.5 KiB
Mobile Innovation with React Native, ComponentKit, and Litho `div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3 > img.video_v06Q`	img.youtube.com/vi/NCAY0HIfrwc/maxresdefault.jpg	44.1 KiB	40.6 KiB

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
reactnative.dev/assets/css/styles.5393e7c0.css	31.7 KiB

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

Element	Layout shift score
div.container_b02U > div.backgroundContainer_Huei > div.devices_vH96 > svg.svgContent_v9JU `div.container_b02U > div.backgroundContainer_Huei > div.devices_vH96 > svg.svgContent_v9JU`	0.105
Development Contributing Community Showcase Blog Search `div#__docusaurus > nav.theme-layout-navbar > div.navbar__inner > div.theme-layout-navbar-right`	0.003
Follow @reactnative `a.twitter-follow-button`	0.000

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.

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

Estimated savings: 40 ms 42.9 KiB

URL	Transfer Size	Est Savings
ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.js	82.4 KiB	39.3 KiB
/collect/website/js/tRaiETqnLgj758hTBazgd8ryO5qrZo8Exadq9...	15.4 KiB	3.6 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 160.4 KiB

URL	Transfer Size	Est Savings
www.googletagmanager.com/gtag/js?id=G-58L13S6BDP	141.9 KiB	62.2 KiB
ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.js	82.4 KiB	50.7 KiB
reactnative.dev/assets/js/main.f6a6aa6b.js	243.3 KiB	47.5 KiB

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

Failure reason	Failure type
The page has an unload handler in a sub frame.	Actionable

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

URL	Transfer Size
reactnative.dev/img/homepage/dissection.png	287.0 KiB
reactnative.dev/img/homepage/dissection-dark.png	277.8 KiB
reactnative.dev/assets/js/main.f6a6aa6b.js	243.4 KiB
reactnative.dev/	183.0 KiB
reactnative.dev/assets/js/1df93b7f.a1a1db4e.js	178.5 KiB
www.googletagmanager.com/gtag/js?id=G-58L13S6BDP	142.2 KiB
/assets/images/cta-bg-pattern-2d71376cb45831f0706617efae8...	140.8 KiB
reactnative.dev/img/showcase/amazon-shopping.png	136.6 KiB
img.youtube.com/vi/NiYwlvXsBKw/maxresdefault.jpg	131.1 KiB
reactnative.dev/img/homepage/tools.png	130.9 KiB

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

	URL
A React Native UI pointing out native elements like Views, ScrollViews, and more `div#__docusaurus_skipToContent_fallback > div.wrapper_Wq0p > div.container_M3fB > img.flyoutIllustration_r9BI`	reactnative.dev/img/homepage/dissection.png
Android device and iOS device `div.platformsContainer_LdgS > div.featureContainer_vkjP > div.deviceContainer_D11o > img.devices_CEHn`	reactnative.dev/img/homepage/devices.png
File system with folders and files representing screens and navigation `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/file-based-routing.png
Grid of icons representing libraries, SDKs, and native code `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/libraries.png
List of developer tool toggles for debugging, performance, and more `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/tools.png
Facebook `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/facebook.webp
Microsoft Office `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/officemobile.png
Microsoft Teams `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/teamsmobile.png
Xbox Game Pass `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/xboxgamepass.png
Shop: All your favorite brands `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/shop.webp
PUMA `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/puma.png
PlayStation App `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/playstation.png
WordPress - Website Builder `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/wordpress.png
Bolt Food: Delivery & Takeaway `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/bolt.png
Klarna \| Shop now. Pay later. `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/klarna.jpg
NFL `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/nfl.webp
Microsoft Outlook `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/outlookmobile.png
Amazon Shopping `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/amazon-shopping.png
Tableau `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/tableau.webp
Mattermost `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/mattermost.webp
Meta Horizon `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/metahorizon.webp
Shopify `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/shopify.png
Tesla `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/tesla.png
FlipKart `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/flipkart.png
Facebook Ads Manager `div > ul.AppList > li.item > img`	reactnative.dev/img/showcase/adsmanager.png
Coinbase `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/coinbase.png
Mercari `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/mercari.png
Bloomberg `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/bloomberg.png
Discord `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/discord.png
Meta Open Source Logo `div.footer__bottom > div.margin-bottom--sm > a.footerLogoLink_tutC > img.footer__logo`	reactnative.dev/img/oss_logo.svg
Messenger Desktop `ul.AppList > li.item > a > img`	reactnative.dev/img/showcase/messengerdesktop.png
div.theme-layout-navbar-left > a.navbar__brand > div.navbar__logo > img.themedComponent_siVc `div.theme-layout-navbar-left > a.navbar__brand > div.navbar__logo > img.themedComponent_siVc`	reactnative.dev/img/header_logo.svg

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

●Document request latency

●Optimize DOM size

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Reduce unused CSS

●User Timing marks and measures 5 user timings

●JavaScript execution time 0.6 s

●Minimizes main-thread work 1.2 s

●Avoid long main-thread tasks 5 long tasks found

●Network Requests

●Network Round Trip Times 20 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 10 ms

○INP breakdown

○LCP request discovery

○Avoid non-composited animations

Accessibility

Contrast

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

Failing Elements
Search `div.navbarSearchContainer_bzqh > button.DocSearch > span.DocSearch-Button-Container > span.DocSearch-Button-Placeholder`

These are opportunities to improve the legibility of your content.

Navigation

Failing Elements
React Native brings the best parts of developing with React to native developme… `div.wrapper_Wq0p > div.container_M3fB > div.container_li6i > h3.description_wtc5`
React Native lets you create truly native apps and doesn't compromise your user… `div.wrapper_Wq0p > div.container_M3fB > div.container_li6i > h3.description_wtc5`
React Native brings the React programming paradigm to platforms like Android an… `div.wrapper_Wq0p > div.container_M3fB > div.container_li6i > h3.description_wtc5`
Watch talks by the React team and learn how to get the most out of React Native… `div.wrapper_Wq0p > div.container_M3fB > div.container_li6i > h3.description_wtc5`

These are opportunities to improve keyboard navigation in your application.

Best practices

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

Failing Elements
html.plugin-pages `html.plugin-pages`

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.

Failing Elements
Why React Native? 1:42 `div.wrapper_Wq0p > div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3`
React Conf 2025 React Native Keynote 55:13 `div.wrapper_Wq0p > div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3`
React Conf 2024 React Native Keynote 55:14 `div.wrapper_Wq0p > div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3`
FB 2019 Mobile innovation with React Native 45:29 `div.wrapper_Wq0p > div.container_M3fB > div.videos_uQz0 > div.videoContainer_A4x3`

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` attributes match their roles

●`[aria-hidden="true"]` is not present on the document `<body>`

●`[role]`s have all required `[aria-*]` attributes

●`[role]` values are valid

●`[aria-*]` attributes have valid values

●`[aria-*]` attributes are valid and not misspelled

●Buttons have an accessible name

●Image elements have `[alt]` attributes

●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.

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

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

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

●Elements use only permitted ARIA attributes

●Document has a `<title>` element

●`<frame>` or `<iframe>` elements have a title

●`<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

●Touch targets have sufficient size and spacing.

●Deprecated ARIA roles were not used

●Identical links have the same purpose.

○`[accesskey]` values are unique

○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

○`<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.

○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.

○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.

Best Practices

User Experience

Image display dimensions should match natural aspect ratio. Learn more about image aspect ratio.

	URL	Aspect Ratio (Displayed)	Aspect Ratio (Actual)
File system with folders and files representing screens and navigation `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/file-based-routing.png	297 x 155 (1.92)	699 x 351 (1.99)
Grid of icons representing libraries, SDKs, and native code `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/libraries.png	297 x 155 (1.92)	699 x 350 (2.00)
List of developer tool toggles for debugging, performance, and more `div.container_M3fB > div.cardContainer_eNmC > div.card_w3eG > img.cardImage_mNuV`	reactnative.dev/img/homepage/tools.png	297 x 155 (1.92)	698 x 350 (1.99)

General

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

Deprecation / Warning	Source
Unload event listeners are deprecated and will be removed.	ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.js line 1071, col 10

URL	Map URL
reactnative.dev/assets/js/main.f6a6aa6b.js
cdn.jsdelivr.net/npm/focus-visible@5.2.0/dist/focus-visible.min.js	cdn.jsdelivr.net/npm/focus-visible@5.2.0/dist/focus-visible.min.js.map

●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

●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 clickjacking with XFO or CSP

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

○Redirects HTTP traffic to HTTPS

100

SEO

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`

Results for https://reactnative.dev

Site Health

Top Priorities (5)

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Navigation

Best practices

Best Practices

User Experience

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