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Lighthouse Mobile

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

Audit breakdown by category with detailed findings.

67

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.
title: Preconnected origins
value: no origins were preconnected
description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.
title: Preconnect candidates
value: No additional origins are good candidates for preconnecting

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer SizeDuration
www.w3schools.com/lib/topnav/main.v1.0.95.js92.0 KiB453 ms
www.w3schools.com/lib/my-learning/main.v1.0.81.js20.8 KiB151 ms
www.w3schools.com/lib/common-deps/main.v1.0.18.js9.3 KiB
www.w3schools.com/lib/user-session/main.v1.0.51.js10.8 KiB
www.w3schools.com/lib/uic.js?v=1.1.03.0 KiB151 ms
www.w3schools.com/lib/uic_prov.js?v=1.4.83.7 KiB
www.w3schools.com/lib/w3schools.css?v=1.0.115.0 KiB
www.w3schools.com/plus/plans/main.v1.0.3.css2.6 KiB
www.w3schools.com/lib/pathfinder/main.v1.0.12.css4.5 KiB151 ms
www.w3schools.com/lib/sparteo.css?v=1.0.5704 B
www.w3schools.com/lib/my-learning/main.v1.0.81.css3.0 KiB
www.w3schools.com/lib/topnav/main.v1.0.95.css15.9 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

RequestCache TTLTransfer Size
static.fastcmp.com/fast-cmp-stub.modern.b8d64b2fce5dae2bd026.js800.0 s61.3 KiB
static.fastcmp.com/fast-cmp-en-tcfeuv2.82b16153b940a36e2f80.js800.0 s53.7 KiB
sync.sparteo.com/crossfire.js14400.0 s12.7 KiB
static.fastcmp.com/fast-cmp-stub.js800.0 s1.7 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
header.fast-cmp-layout-header > div.fast-cmp-layout-header__container > div.fast-cmp-layout-header__box > img header.fast-cmp-layout-header > div.fast-cmp-layout-header__container > div.fast-cmp-layout-header__box > img
www.w3schools.com/images/w3schools_logo_500_04AA6D.webp7.2 KiB7.0 KiB

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

Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 783 ms
URLTime Spent
w3schools.com/783 ms
www.w3schools.com/0.0 ms

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Diagnostics

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 150 ms 40.0 KiB
URLTransfer SizeEst Savings
www.w3schools.com/lib/topnav/main.v1.0.95.js91.6 KiB25.1 KiB
www.w3schools.com/lib/my-learning/main.v1.0.81.js20.4 KiB6.0 KiB
www.w3schools.com/lib/w3schools_footer.js?update=2025092414.6 KiB3.7 KiB
www.w3schools.com/lib/user-session/main.v1.0.51.js10.4 KiB2.9 KiB
www.w3schools.com/lib/common-deps/main.v1.0.18.js8.9 KiB2.3 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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 27.9 KiB
URLTransfer SizeEst Savings
www.w3schools.com/lib/topnav/main.v1.0.95.css15.5 KiB14.5 KiB
www.w3schools.com/lib/w3schools.css?v=1.0.114.7 KiB13.4 KiB

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 300 ms 461.0 KiB
URLTransfer SizeEst Savings
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js361.8 KiB241.8 KiB
www.googletagmanager.com/gtag/js?id=G-9YNMTB56NB&cx=c&gtm=4e64f0h1174.6 KiB70.3 KiB
www.w3schools.com/lib/topnav/main.v1.0.95.js91.6 KiB67.9 KiB
www.googletagmanager.com/gtm.js?id=GTM-KTCFC3S126.8 KiB59.4 KiB
static.fastcmp.com/fast-cmp-stub.modern.b8d64b2fce5dae2bd026.js61.2 KiB21.6 KiB

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Script Evaluation964 ms
Other421 ms
Script Parsing & Compilation323 ms
Style & Layout253 ms
Parse HTML & CSS90 ms
Rendering54 ms

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Checkmark div > ul > li > img
www.w3schools.com/spaces/files/check3.db67d31e.svg
Frontend Code Editor div.codeeditorbr-container > div#Frontend > picture > img
Dynamic Spaces div.w3-center > div > picture > img
Classroom div.w3-col > a > picture > img
W3.CSS Templates div.w3-content > a > picture > img

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

●Layout shift culprits
●Optimize DOM size
●Font display
●Forced reflow
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●Minify CSS
●Avoids enormous network payloads Total size was 1,407 KiB
●User Timing marks and measures 5 user timings
●JavaScript execution time 1.2 s
●Avoid long main-thread tasks 11 long tasks found
●Avoid non-composited animations 1 animated element found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 40 ms
●Server Backend Latencies 30 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 10 ms
○INP breakdown
○LCP request discovery
○Avoid large layout shifts
92

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

Contrast

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Sign In div#pagetop > div.tnb-right-section > div#tnb-login-btn > span.button-text
Learn HTML div.w3-row > div.w3-content > div.w3-col > a.w3-button
Learn CSS div.w3-row > div.w3-content > div.w3-col > a.w3-button
Learn JavaScript div.w3-row > div.w3-content > div.w3-col > a.w3-button
Learn Python div.w3-row > div.w3-content > div.w3-col > a.w3-button
Learn SQL div.w3-row > div.w3-content > div.w3-col > a.w3-button
Sign Up div.w3-row > div.w3-center > p > a#myLearningFromDefault
Try Frontend Editor (HTML/CSS/JS) div#main > div.ws-black > div.w3-content > a.ws-btn
Learn More div#main > div.w3-center > div > a.ws-btn
Learn More div.w3-row > div#main > div.pro-caption > a#proFromDefault
Learn More div.pro-caption > div.w3-content > div.w3-col > a.w3-button
Exercises div.w3-row-padding > div.w3-half > p > a.w3-button
Get started div#main > div#getdiploma > div > a.w3-btn

These are opportunities to improve the legibility of your content.

Navigation

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
With the world's largest web developer site. div#main > div.ws-black > div.w3-content > h3.learntocodeh3
A web server programming language div.w3-col > div.w3-card-2 > div > h5.w3-text-dark-grey
A JS library for developing web pages div.w3-col > div.w3-card-2 > div > h5.w3-text-dark-grey
A programming language div.w3-col > div.w3-card-2 > div > h5.w3-text-dark-grey
A programming language div.w3-col > div.w3-card-2 > div > h5.w3-text-dark-grey
A CSS framework for faster and better responsive web pages div.w3-col > div.w3-card-2 > div > h5
A CSS framework for designing better web pages div.w3-col > div.w3-card-2 > div > h5.w3-text-dark-grey
Create an account to track your progress, get your own website,and get access t… div#main > div.w3-row > div.w3-center > h4
With our online code editor, you can edit code and view the result in your brow… div#main > div.ws-black > div.w3-content > h4.w3-center
If you want to create your own website, check out W3Schools Spaces. div#main > div.w3-center > div > h3
No installation required - just open your browser and start coding: div#main > div.w3-center > div > h5
And unlock powerful features: div.w3-row > div#main > div.pro-caption > h3
W3Schools' famous color picker: div#main > div.w3-center > div.w3-content > h4
Test your skills! div.w3-row > div#main > div.w3-center > h4
Browse our selection of free responsive HTML Templates div.w3-row > div#main > div.w3-center > h4
Code snippets for HTML, CSS and JavaScript div.w3-row > div#main > div#howto_padding > h4.xxw3-text-dark-grey
For example, how to create a slideshow: div.w3-row > div#main > div#howto_padding > h6

These are opportunities to improve keyboard navigation in your application.

Best practices

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. Learn more about touch targets.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
HTML Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
CSS Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
JavaScript Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
How To Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
SQL Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Python Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
W3.CSS Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Bootstrap Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
PHP Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Java Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
C++ Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
jQuery Tutorial div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
HTML Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
CSS Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
JavaScript Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
SQL Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Python Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
W3.CSS Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Bootstrap Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
PHP Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
HTML Colors div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Java Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
AngularJS Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
jQuery Reference div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
HTML Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
CSS Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
JavaScript Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
How To Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
SQL Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Python Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
W3.CSS Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Bootstrap Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
PHP Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Java Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
XML Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
jQuery Examples div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
HTML Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
CSS Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
JavaScript Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Front End Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
SQL Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Python Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
PHP Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
jQuery Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
Java Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
C++ Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
C# Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom
XML Certificate div#spacemyfooter > div > div.footerlinks_2 > a.ga-bottom

These items highlight common accessibility best practices.

○Interactive controls are keyboard focusable
○Interactive elements indicate their purpose and state
○The page has a logical tab order
○Visual order on the page follows DOM order
○User focus is not accidentally trapped in a region
○The user's focus is directed to new content added to the page
○HTML5 landmark elements are used to improve navigation
○Offscreen content is hidden from assistive technology
○Custom controls have associated labels
○Custom controls have ARIA roles
●`[aria-*]` attributes match their roles
●`[aria-hidden="true"]` is not present on the document `<body>`
●`[role]`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.
●`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
●No element has a `[tabindex]` value greater than 0
●Document has a main landmark.
●Deprecated ARIA roles were not used
●Identical links have the same purpose.
●Elements with visible text labels have matching accessible names.
○`[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
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○Skip links are focusable.
○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
○`[lang]` attributes have a valid value
○`<video>` elements contain a `<track>` element with `[kind="captions"]`
○Tables have different content in the summary attribute and `<caption>`.
○All heading elements contain content.
○Uses ARIA roles only on compatible elements
○Image elements do not have `[alt]` attributes that are redundant text.
○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
○`<td>` elements in a large `<table>` have one or more table headers.
100

Best Practices

●Uses HTTPS
●Avoids deprecated APIs
●Avoids third-party cookies
●Allows users to paste into input fields
●Avoids requesting the geolocation permission on page load
●Avoids requesting the notification permission on page load
●Displays images with correct aspect ratio
●Serves images with appropriate resolution
●Page has the HTML doctype
●Properly defines charset
●No browser errors logged to the console
●No issues in the `Issues` panel in Chrome Devtools
●Ensure CSP is effective against XSS attacks
●Use a strong HSTS policy
●Ensure proper origin isolation with COOP
●Mitigate DOM-based XSS with Trusted Types
●Detected JavaScript libraries
●Page has valid source maps
○Redirects HTTP traffic to HTTPS
○Mitigate clickjacking with XFO or CSP
83

SEO

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

Content Best Practices

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Link destinationLink Text
www.w3schools.com/go/go_exercises.phpGo
www.w3schools.com/go/index.phpGO
www.w3schools.com/go/index.phpGo
www.w3schools.com/spaces/index.phpLearn More
order.w3schools.com/plansLearn More
www.w3schools.com/academy/index.phpLearn More

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

Crawling and Indexing

Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. Learn how to make links crawlable

Why this matters

Performance issues directly impact user engagement and conversion rates.

Uncrawlable Link
div#subtopnav > div#menubtn_container > span > a.topnav-icons div#subtopnav > div#menubtn_container > span > a.topnav-icons
body.w3s-user-anonymous > div.topnavcontainer > div#subtopnav > a body.w3s-user-anonymous > div.topnavcontainer > div#subtopnav > a
CONTACT US div#spacemyfooter > div > div.footerlinks_1 > a
cookies div#footerwrapper > div#spacemyfooter > div.footertext > a.ga-bottom

To appear in search results, crawlers need access to your app.

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

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