Lighthouse Mobile

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

SCORE

GRADE

FIX

REVIEW

PASS

INFO

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.

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.

Request	Cache TTL	Transfer Size
/signals/config/1148425983053697?v=2.9.303&r=stable&domai...	1200.0 s	126.7 KiB
/resource-blocker/83c28410-26f6-4523-a7d3-466c377cb83f?au...	14400.0 s	143.4 KiB
connect.facebook.net/en_US/fbevents.js	1200.0 s	99.4 KiB
www.redditstatic.com/ads/pixel.js	60.0 s	19.0 KiB
/signals/config/1868037393206637?v=2.9.303&r=stable&domai...	1200.0 s	18.5 KiB
/signals/config/1353221701695684?v=2.9.303&r=stable&domai...	1200.0 s	16.9 KiB
pixel.byspotify.com/ping.min.js	3600.0 s	10.3 KiB
snap.licdn.com/li.lms-analytics/insight.min.js	86400.0 s	18.7 KiB
bat.bing.com/p/conversions/s/0.8.59	86400.0 s	15.6 KiB
app.termly.io/resource-blocker/support/894-6156b36a131577c56e7e.min.js	14400.0 s	8.4 KiB
app.termly.io/resource-blocker/support/808-26e9c6c7a3bd048ed656.min.js	14400.0 s	3.2 KiB
app.termly.io/resource-blocker/support/524-7d36cb122791702e3df2.min.js	14400.0 s	2.7 KiB
/collect?v=2&fmt=js&pid=4378410&time=1776819336671&url=ht...	0.0 ms	691 B
/rp.gif?ts=1776819336875&id=a2_h9e57mmhk0gb&event=PageVis...	0.0 ms	666 B
app.termly.io/resource-blocker/support/377-e518d8a5c599aa1c5977.min.js	14400.0 s	873 B
/config/uk/01c2b1dd-571f-44c3-bfae-8bdeebe23c07.js?v=3.55...	0.0 ms	473 B
/collect?v=2&fmt=js&pid=6441714%2C4378410&time=1776819336...	0.0 ms	388 B
dev.visualwebsiteoptimizer.com/lib/677629.js	0.0 ms	266 B
/tr/?id=1148425983053697&ev=PageView&dl=https%3A%2F%2Fwww...	0.0 ms	16 B
/tr/?id=1868037393206637&ev=PageView&dl=https%3A%2F%2Fwww...	0.0 ms	16 B
/tr/?id=1353221701695684&ev=PageView&dl=https%3A%2F%2Fwww...	0.0 ms	16 B

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.

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.

	URL	Resource Size	Est Savings
Crematogaster ant on Macaranga plant `article.news-block > div.news-block__image > div.image > img`	www.qmul.ac.uk/media/qmul/media/news/items/se/2026/ant-news-large.png	365.2 KiB	350.1 KiB
article.news-block > div.news-block__image > div.image > img `article.news-block > div.news-block__image > div.image > img`	www.qmul.ac.uk/media/qmul/media/news/items/fmd/Kidney-640.png	341.5 KiB	325.8 KiB
div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img `div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img`	www.qmul.ac.uk/media/qmul/postgraduate/students_600x400.jpg	109.4 KiB	93.8 KiB
Interior of The Octagon on Queen Mary's Mile End campus `section#main-content > section.hero-slat > div.hero-slat__img > img.hero-slat__image`	/prod01/channel_262/queen-mary-university-of-london/media...	117.8 KiB	92.2 KiB
Student on a laptop `div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img`	/media/qmul/undergraduate/feesandfunding/20241004_QMU_168...	70.1 KiB	54.4 KiB
Return to the Queen Mary University of London homepage `header#top > div.header__container > a.header__logo > img.QM-Logo-New`	/media/ow-assets/assets/icons/Queen-Mary_Est_1785_RGB_Whi...	25.8 KiB	25.4 KiB

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-3-IMG

nodeLabel: Interior of The Octagon on Queen Mary's Mile End campus

path: 1,HTML,1,BODY,7,SECTION,1,SECTION,0,DIV,0,IMG

selector: section#main-content > section.hero-slat > div.hero-slat__img > img.hero-slat__image

snippet: <img class="hero-slat__image" srcset="https://pxl-qmulacuk.terminalfour.net/prod01/channel_262/queen-mary-univer…" sizes="(min-width: 1900px) 1800px, calc(94.94vw + 15px)" src="https://pxl-qmulacuk.terminalfour.net/prod01/channel_262/queen-mary-univer…" alt="Interior of The Octagon on Queen Mary's Mile End campus">

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

title: Preconnected origins

value: no origins were preconnected

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

title: Preconnect candidates

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size	Duration
dev.visualwebsiteoptimizer.com/lib/677629.js	266 B	820 ms
www.qmul.ac.uk/media/ow-assets/assets/css/lib.min.1.3.css?version=11.0	117.9 KiB	1.2 s
www.qmul.ac.uk/media/ow-assets/assets/css/qm-custom.1.3.css?version=17.0	6.7 KiB
www.qmul.ac.uk/media/ow-assets/assets/css/t4extra.css?version=6.0	1.9 KiB
www.qmul.ac.uk/media/ow-assets/assets/css/vendors~lib.min.1.2.4.css?version=2.0	4.5 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: 787 ms

URL	Time Spent
qmul.ac.uk/	787 ms
www.qmul.ac.uk/	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 CSS files can reduce network payload sizes. Learn how to minify CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 35.9 KiB

URL	Transfer Size	Est Savings
www.qmul.ac.uk/media/ow-assets/assets/css/lib.min.1.3.css?version=11.0	117.9 KiB	35.9 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: 750 ms 113.5 KiB

URL	Transfer Size	Est Savings
www.qmul.ac.uk/media/ow-assets/assets/css/lib.min.1.3.css?version=11.0	116.7 KiB	113.5 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: 2.4 s 458.8 KiB

URL	Transfer Size	Est Savings
analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwMQ.js	109.2 KiB	84.6 KiB
www.googletagmanager.com/gtag/js?id=AW-16588318700&cx=c&gtm=4e64h1	144.8 KiB	81.3 KiB
www.googletagmanager.com/gtm.js?id=GTM-KQZ3W5	196.6 KiB	66.7 KiB
analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwOA.js	116.8 KiB	60.6 KiB
/resource-blocker/83c28410-26f6-4523-a7d3-466c377cb83f?au...	143.2 KiB	54.3 KiB
www.qmul.ac.uk/media/ow-assets/assets/js/vendors~lib.min.1.2.4.js	51.7 KiB	42.5 KiB
/signals/config/1148425983053697?v=2.9.303&r=stable&domai...	125.5 KiB	35.9 KiB
connect.facebook.net/en_US/fbevents.js	96.5 KiB	33.0 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Total CPU Time	Script Evaluation	Script Parse
www.googletagmanager.com/gtm.js?id=GTM-KQZ3W5	421 ms	349 ms	60 ms
Unattributable	406 ms	95 ms	0.0 ms
www.redditstatic.com/ads/pixel.js	383 ms	343 ms	5.4 ms
/resource-blocker/83c28410-26f6-4523-a7d3-466c377cb83f?au...	308 ms	247 ms	48 ms
www.qmul.ac.uk/	269 ms	14 ms	3.4 ms
analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwOA.js	255 ms	207 ms	45 ms
/signals/config/1148425983053697?v=2.9.303&r=stable&domai...	214 ms	184 ms	29 ms
www.googletagmanager.com/gtag/js?id=AW-16588318700&cx=c&gtm=4e64h1	127 ms	96 ms	30 ms
connect.facebook.net/en_US/fbevents.js	117 ms	82 ms	34 ms
sc-static.net/scevent.min.js	101 ms	90 ms	5.2 ms
analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwMQ.js	100 ms	43 ms	57 ms
www.qmul.ac.uk/media/ow-assets/assets/js/jquery.min.js	66 ms	48 ms	5.7 ms
/signals/config/1353221701695684?v=2.9.303&r=stable&domai...	60 ms	47 ms	7.1 ms
bat.bing.com/p/conversions/s/0.8.59	57 ms	26 ms	3.2 ms
/signals/config/1868037393206637?v=2.9.303&r=stable&domai...	53 ms	41 ms	9.0 ms
snap.licdn.com/li.lms-analytics/insight.min.js	51 ms	40 ms	4.8 ms

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Category	Time Spent
Script Evaluation	2.1 s
Script Parsing & Compilation	396 ms
Other	394 ms
Style & Layout	195 ms
Parse HTML & CSS	70 ms
Rendering	29 ms
Garbage Collection	25 ms

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size
www.qmul.ac.uk/media/qmul/media/news/items/se/2026/ant-news-large.png	366.7 KiB
www.qmul.ac.uk/media/qmul/media/news/items/fmd/Kidney-640.png	343.0 KiB
www.googletagmanager.com/gtm.js?id=GTM-KQZ3W5	197.0 KiB
www.googletagmanager.com/gtag/js?id=AW-16588318700&cx=c&gtm=4e64h1	144.9 KiB
/resource-blocker/83c28410-26f6-4523-a7d3-466c377cb83f?au...	143.4 KiB
/signals/config/1148425983053697?v=2.9.303&r=stable&domai...	126.7 KiB
/prod01/channel_262/queen-mary-university-of-london/media...	118.5 KiB
www.qmul.ac.uk/media/ow-assets/assets/css/lib.min.1.3.css?version=11.0	117.9 KiB
analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwOA.js	117.4 KiB
www.qmul.ac.uk/media/qmul/postgraduate/students_600x400.jpg	110.7 KiB

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
div.slat__container > ul.stats__list > li.grid__item > img.stats__logo `div.slat__container > ul.stats__list > li.grid__item > img.stats__logo`	www.qmul.ac.uk/media/ow-assets/assets/icons/Russell-Group_White.png
Return to the Queen Mary University of London homepage `header#top > div.header__container > a.header__logo > img.QM-Logo-New`	/media/ow-assets/assets/icons/Queen-Mary_Est_1785_RGB_Whi...
Crematogaster ant on Macaranga plant `article.news-block > div.news-block__image > div.image > img`	www.qmul.ac.uk/media/qmul/media/news/items/se/2026/ant-news-large.png
article.news-block > div.news-block__image > div.image > img `article.news-block > div.news-block__image > div.image > img`	www.qmul.ac.uk/media/qmul/media/news/items/fmd/Kidney-640.png

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 JavaScript

●User Timing marks and measures 1 user timing

●Avoid long main-thread tasks 12 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 20 ms

●Server Backend Latencies 190 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 0 ms

●Avoid large layout shifts 1 layout shift found

○INP breakdown

○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.

Names and labels

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img `div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img`
div.featured-slat__container > div.featured-slat__content > div.featured-slat__image > img.featured-slat__img `div.featured-slat__container > div.featured-slat__content > div.featured-slat__image > img.featured-slat__img`
div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img `div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img`

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

Best practices

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.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
View profile `footer.featured-card__footer > figure.featured-card__content > figcaption.featured-card__profile > a.featured-card__link`

○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

●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.

●Select elements have associated label elements.

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

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

●Elements with `role="dialog"` or `role="alertdialog"` have accessible names.

●`[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

●`<html>` element has a `[lang]` attribute

●`<html>` element has a valid value for its `[lang]` attribute

●Links have a discernible name

●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

●No element has a `[tabindex]` value greater than 0

●Touch targets have sufficient size and spacing.

●Heading elements appear in a sequentially-descending order

●Skip links are focusable.

●Deprecated ARIA roles were not used

○`[accesskey]` values are unique

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.

○`[role]`s are contained by their required parent element

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

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

○The page contains a heading, skip link, or landmark region

○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.

○Definition list items are wrapped in `<dl>` elements

○ARIA IDs are unique

○No form fields have multiple labels

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

○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.

○Input buttons have discernible text.

○`<input type="image">` elements have `[alt]` text

○Links are distinguishable without relying on color.

○The document does not use `<meta http-equiv="refresh">`

○`<object>` elements have alternate text

○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.

○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

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Deprecation / Warning	Source
AttributionReporting	snap.licdn.com/li.lms-analytics/insight.min.js

●Uses HTTPS

●Avoids third-party cookies

●Allows users to paste into input fields

●Avoids requesting the geolocation permission on page load

●Avoids requesting the notification permission on page load

●Displays images with correct aspect ratio

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

●No 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

SEO

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

Content Best Practices

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img `div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img`
div.featured-slat__container > div.featured-slat__content > div.featured-slat__image > img.featured-slat__img `div.featured-slat__container > div.featured-slat__content > div.featured-slat__image > img.featured-slat__img`
div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img `div.highlight-cards__item > article.highlight-card > div.highlight-card__image > img`

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

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●Document has a valid `hreflang`

○robots.txt is valid

○Document has a valid `rel=canonical`