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Lighthouse Mobile

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

Audit breakdown by category with detailed findings.

99

Performance

Insights

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

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.

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.

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: 802 ms
URLTime Spent
random.org/802 ms
www.random.org/0.0 ms
Layout shift culprits
Optimize DOM size
Font display
Forced reflow
Improve image delivery
LCP breakdown
Modern HTTP
Optimize viewport for mobile
Time to Interactive 1.6 s
Max Potential First Input Delay 20 ms
Minify CSS
Minify JavaScript
Reduce unused CSS
Reduce unused JavaScript
Avoids enormous network payloads Total size was 56 KiB
JavaScript execution time 0.0 s
Minimizes main-thread work 0.3 s
Image elements have explicit `width` and `height`
Page didn't prevent back/forward cache restoration
Network Requests
Network Round Trip Times 20 ms
Server Backend Latencies 20 ms
Tasks
Diagnostics
Metrics
Screenshot Thumbnails
Final Screenshot
Script Treemap Data
Resources Summary
Initial server response time was short Root document took 50 ms
INP breakdown
LCP request discovery
User Timing marks and measures
Avoid long main-thread tasks
Avoid non-composited animations
Avoid large layout shifts
65

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
Search RANDOM.ORG div#invisible > div#search > form > div
What's this fuss about true randomness? body > div#invisible > div#homepage-wide-column > h2
true div#invisible > div#homepage-wide-column > h2 > em
Prof. Mads Haahr div#invisible > div#homepage-wide-column > p > a
School of Computer Science and Statistics div#invisible > div#homepage-wide-column > p > a
Trinity College, Dublin div#invisible > div#homepage-wide-column > p > a
Randomness and Integrity Services Ltd div#invisible > div#homepage-wide-column > p > a
Games and Lotteries div > div.mainindent > h3 > a
Lottery Quick Pick div > div.mainindent > p > a
Keno Quick Pick div > div.mainindent > p > a
Coin Flipper div > div.mainindent > p > a
Dice Roller div > div.mainindent > p > a
Playing Card Shuffler div > div.mainindent > p > a
Birdie Fund Generator div > div.mainindent > p > a
Random Drawings div > div.mainindent > h3 > a
Q3.1 in the FAQ div > div.mainindent > p > a
Third-Party Draw Service div > div.mainindent > p > a
Step by Step Guide div > div.mainindent > p > a
Step by Step Video div > div.mainindent > p > a
Price Calculator div > div.mainindent > p > a
Drawing FAQ div > div.mainindent > p > a
Public Records div > div.mainindent > p > a
Drawing Result Widget div > div.mainindent > p > a
Multi-Round Giveaway Service div > div.mainindent > p > a
Numbers div > div.mainindent > h3 > a
Integer Generator div > div.mainindent > p > a
Sequence Generator div > div.mainindent > p > a
Integer Set Generator div > div.mainindent > p > a
Gaussian Generator div > div.mainindent > p > a
Decimal Fraction Generator div > div.mainindent > p > a
Raw Random Bytes div > div.mainindent > p > a
Lists and Strings and Maps, Oh My! div > div.mainindent > h3 > a
List Randomizer div > div.mainindent > p > a
String Generator div > div.mainindent > p > a
Password Generator div > div.mainindent > p > a
Clock Time Generator div > div.mainindent > p > a
Calendar Date Generator div > div.mainindent > p > a
Geographic Coordinate Generator div > div.mainindent > p > a
Bitmaps div > div.mainindent > p > a
Hexadecimal Color Code Generator div > div.mainindent > p > a
Pregenerated Files div > div.mainindent > p > a
Pure White Audio Noise div > div.mainindent > p > a
Jazz Scales div > div.mainindent > p > a
Samuel Beckett div > div.mainindent > p > a
DNA Protein Sequence Randomizer div > div.mainindent > p > a
Web Tools and Widgets for Your Pages div > div.mainindent > h3 > a
Integer Widget Wizard div > div.mainindent > p > a
Draw Widget Wizard div > div.mainindent > p > a
HTTP API div > div.mainindent > p > a
Guidelines div > div.mainindent > p > a
Banned Hosts div > div.mainindent > p > a
Learn about Randomness div > div.mainindent > h3 > a
Introduction to Randomness div > div.mainindent > p > a
History div > div.mainindent > p > a
Many Testimonials div > div.mainindent > p > a
Acknowledgements div > div.mainindent > p > a
Quotations div > div.mainindent > p > a
Media Coverage and Scientific Citations div > div.mainindent > p > a
News div > div.mainindent > p > a
Statistics div > div.mainindent > h3 > a
Real-Time Statistics div > div.mainindent > p > a
Statistical Analysis div > div.mainindent > p > a
Bit Tally div > div.mainindent > p > a
Your Quota div > div.mainindent > p > a
Contact and Help div#invisible > div > div.mainindent > h3
FAQ div > div.mainindent > p > a
Newsletter div > div.mainindent > p > a
Contact Details div > div.mainindent > p > a
BlueSky div#invisible > div > div > a
Terms and Conditions div#invisible > div > div > a
About Us div#invisible > div > div > a

These are opportunities to improve the legibility of your content.

Names and labels

Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more about form element labels.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div#search > form > div > input div#search > form > div > input

Screen reader users rely on frame titles to describe the contents of frames. Learn more about frame titles.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
body > div#invisible > div#homepage-generator > iframe body > div#invisible > div#homepage-generator > iframe

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Internationalization and localization

If a page doesn't specify a `lang` attribute, a screen reader assumes that the page is in the default language that the user chose when setting up the screen reader. If the page isn't actually in the default language, then the screen reader might not announce the page's text correctly. Learn more about the `lang` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html html

These are opportunities to improve the interpretation of your content by users in different locales.

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
Home div#invisible > ul#navigation > li > a.active
Games div#invisible > ul#navigation > li > a
Numbers div#invisible > ul#navigation > li > a
Lists & More div#invisible > ul#navigation > li > a
Drawings div#invisible > ul#navigation > li > a
Web Tools div#invisible > ul#navigation > li > a
Statistics div#invisible > ul#navigation > li > a
Testimonials div#invisible > ul#navigation > li > a
Learn More div#invisible > ul#navigation > li > a
Login div#invisible > ul#navigation > li > a
Terms and Conditions div#invisible > div > div > a
About Us div#invisible > div > div > a

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html html

These items highlight common accessibility best practices.

Interactive controls are keyboard focusable
Interactive elements indicate their purpose and state
The page has a logical tab order
Visual order on the page follows DOM order
User focus is not accidentally trapped in a region
The user's focus is directed to new content added to the page
HTML5 landmark elements are used to improve navigation
Offscreen content is hidden from assistive technology
Custom controls have associated labels
Custom controls have ARIA roles
`[aria-hidden="true"]` is not present on the document `<body>`
Input buttons have discernible text.
`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
Document has a `<title>` element
`<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
Heading elements appear in a sequentially-descending order
`[accesskey]` values are unique
`[aria-*]` attributes match their roles
`button`, `link`, and `menuitem` elements have accessible names
ARIA attributes are used as specified for the element's role
Deprecated ARIA roles were not used
Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
`[aria-hidden="true"]` elements do not contain focusable descendents
ARIA input fields have accessible names
ARIA `meter` elements have accessible names
ARIA `progressbar` elements have accessible names
Elements use only permitted ARIA attributes
`[role]`s have all required `[aria-*]` attributes
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
`[role]` values are valid
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
`[aria-*]` attributes have valid values
`[aria-*]` attributes are valid and not misspelled
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
`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
Image elements have `[alt]` attributes
`<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.
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.
Identical links have the same purpose.
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.
92

Best Practices

Browser Compatibility

Specifying a doctype prevents the browser from switching to quirks-mode. Learn more about the doctype declaration.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

SourceDescription
www.random.org/ line 457, col 6
ReferenceError: $ is not defined at https://www.random.org/:458:7
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
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
Page has valid source maps
Redirects HTTP traffic to HTTPS
Use a strong HSTS policy
Mitigate clickjacking with XFO or CSP
Detected JavaScript libraries
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
Document has a valid `hreflang`
Image elements have `[alt]` attributes
Document has a valid `rel=canonical`

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