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
connect.facebook.net/en_US/fbevents.js	1200.0 s	95.0 KiB
/signals/config/1199096620574484?v=2.9.291&r=stable&domai...	1200.0 s	37.2 KiB
/widget/view?schools=stanford&days=31&num=4&sponsored=1&c...	600.0 s	17.7 KiB
www.google-analytics.com/analytics.js	7200.0 s	20.9 KiB
siteimproveanalytics.com/js/siteanalyze_80352.js	86400.0 s	19.7 KiB
static.hotjar.com/c/hotjar-6430056.js?sv=6	60.0 s	6.2 KiB
/tr/?id=1199096620574484&ev=PageView&dl=https%3A%2F%2Fwww...	0.0 ms	19 B

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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Est Savings
/wp-content/themes/homesite17/fonts/fontawesome-webfont.w...	30 ms
/s/sourcesanspro/v23/6xKydSBYKcSV-LCoeQqfX1RYOo3i54rwlxdu...	30 ms
/s/sourcesanspro/v23/6xK1dSBYKcSV-LCoeQqfX1RYOo3qPZ7nsDJB...	25 ms
/s/sourcesanspro/v23/6xKydSBYKcSV-LCoeQqfX1RYOo3ig4vwlxdu...	20 ms
/s/sourcesanspro/v23/6xKydSBYKcSV-LCoeQqfX1RYOo3iu4nwlxdu...	15 ms
www.stanford.edu/wp-content/themes/homesite17/fonts/Stanford.ttf?a9awv8	10 ms
/s/sourcesanspro/v23/6xKydSBYKcSV-LCoeQqfX1RYOo3ik4zwlxdu...	10 ms
/s/sourcesanspro/v23/6xK3dSBYKcSV-LCoeQqfX1RYOo3qOK7lujVj...	5.0 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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

items: [map[reflowTime:1.012 source:map[column:197 line:775 type:source-location url:https://www.googletagmanager.com/gtm.js?id=GTM-T4N2WTT urlProvider:network]]]

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

items: [map[reflowTime:155.2 source:map[type:text value:[unattributed]]] map[reflowTime:1.012 source:map[column:55 line:772 type:source-location url:https://www.googletagmanager.com/gtm.js?id=GTM-T4N2WTT urlProvider:network]]]

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
fonts.googleapis.com/css?family=Open+Sans%3A400%2C300&ver=6.9.1	1.7 KiB	810 ms
/css?family=Source+Sans+Pro:200,200i,300,300i,400,400i,60...	1.3 KiB
fonts.googleapis.com/css?family=Source+Serif+Pro:400,600,700	832 B
fonts.googleapis.com/css?family=Source+Code+Pro	1.1 KiB
www.stanford.edu/wp-includes/js/jquery/jquery.min.js?ver=3.7.1	34.9 KiB	154 ms
www.stanford.edu/wp-content/plugins/stanford-fb-pixel/pixel.js?ver=1.0.1	865 B
www.stanford.edu/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.1	5.5 KiB
/wp-content/themes/homesite17/css/master.min.css?ver=2021...	72.7 KiB	617 ms
www.stanford.edu/wp-content/plugins/site-improve-snippet/snippet.js?ver=1.0	546 B
/wp-content/plugins/formidable/css/formidableforms.css?ve...	30.3 KiB	463 ms
www.stanford.edu/wp-content/themes/homesite17/style.css?ver=6.9.1	602 B
/wp-content/plugins/awesome-weather-pro/awesome-weather.c...	8.6 KiB	154 ms

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
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2022/04/Campus-life-1-767x481.jpg	67.6 KiB	24.3 KiB
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	/wp-content/uploads/2023/03/20220714Hopkins_Marine_Statio...	53.1 KiB	14.8 KiB

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

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

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

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: 770 ms 96.9 KiB

URL	Transfer Size	Est Savings
/wp-content/themes/homesite17/css/master.min.css?ver=2021...	72.4 KiB	66.9 KiB
/wp-content/plugins/formidable/css/formidableforms.css?ve...	30.1 KiB	30.0 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 1.6 s 258.6 KiB

URL	Transfer Size	Est Savings
www.googletagmanager.com/gtm.js?id=GTM-T4N2WTT	158.1 KiB	64.6 KiB
www.googletagmanager.com/gtag/js?id=G-E08J4Q7DG7&cx=c&_slc=1	146.5 KiB	62.8 KiB
www.googletagmanager.com/gtag/js?id=G-RBCPHN00S7&cx=c&gtm=4e6411	146.3 KiB	59.2 KiB
script.hotjar.com/modules.6a0f3932cb1341a35c18.js	56.1 KiB	37.8 KiB
connect.facebook.net/en_US/fbevents.js	94.8 KiB	34.2 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.stanford.edu/	1.4 s	127 ms	29 ms
Unattributable	483 ms	32 ms	0.0 ms
www.googletagmanager.com/gtm.js?id=GTM-T4N2WTT	463 ms	387 ms	66 ms
/wp-content/themes/homesite17/js/dist/master.min.js?ver=2...	329 ms	202 ms	9.1 ms
www.googletagmanager.com/gtag/js?id=G-RBCPHN00S7&cx=c&gtm=4e6411	319 ms	259 ms	57 ms
www.googletagmanager.com/gtag/js?id=G-E08J4Q7DG7&cx=c&_slc=1	307 ms	250 ms	56 ms
js-agent.newrelic.com/nr-spa-1.312.0.min.js	246 ms	201 ms	13 ms
script.hotjar.com/modules.6a0f3932cb1341a35c18.js	205 ms	169 ms	31 ms
connect.facebook.net/en_US/fbevents.js	175 ms	126 ms	47 ms
/signals/config/1199096620574484?v=2.9.291&r=stable&domai...	124 ms	101 ms	22 ms
siteimproveanalytics.com/js/siteanalyze_80352.js	95 ms	83 ms	10 ms
www.stanford.edu/wp-includes/js/jquery/jquery.min.js?ver=3.7.1	91 ms	70 ms	12 ms
/wp-content/themes/homesite17/css/master.min.css?ver=2021...	89 ms	0.0 ms	0.0 ms
www.google-analytics.com/analytics.js	78 ms	66 ms	7.3 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
Style & Layout	922 ms
Other	808 ms
Script Parsing & Compilation	388 ms
Parse HTML & CSS	193 ms
Rendering	75 ms
Garbage Collection	26 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
/photos/45439829176291/square_300@2x/b9be8d5c99a1837d0ece...	163.7 KiB
/photos/52499668886249/square_300@2x/2f8dd4032affbaea19c6...	160.4 KiB
www.googletagmanager.com/gtm.js?id=GTM-T4N2WTT	158.5 KiB
www.googletagmanager.com/gtag/js?id=G-E08J4Q7DG7&cx=c&_slc=1	146.5 KiB
www.googletagmanager.com/gtag/js?id=G-RBCPHN00S7&cx=c&gtm=4e6411	146.3 KiB
connect.facebook.net/en_US/fbevents.js	95.0 KiB
www.stanford.edu/wp-content/uploads/2021/10/dish-andrew-sm-767x681.jpg	77.9 KiB
/wp-content/themes/homesite17/fonts/fontawesome-webfont.w...	75.7 KiB
/wp-content/uploads/2026/03/53206112789-e5e932c583-o-astr...	74.5 KiB
www.stanford.edu/wp-content/uploads/2022/04/Gym-champs-767x479.jpg	73.7 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
section.panel-collection > section#splash-screen > picture > img.bg-img `section.panel-collection > section#splash-screen > picture > img.bg-img`	www.stanford.edu/wp-content/uploads/2023/10/Hero-3-2-767x510.jpg
section.panel-collection > section#khoi-young-25 > picture > img.bg-img `section.panel-collection > section#khoi-young-25 > picture > img.bg-img`	www.stanford.edu/wp-content/uploads/2025/06/Khoi-background-767x384.png
section.panel-collection > section#renee-zhao > picture > img.bg-img `section.panel-collection > section#renee-zhao > picture > img.bg-img`	www.stanford.edu/wp-content/uploads/2025/04/20250320_Renee_Zhao-5-767x511.jpg
section.panel-collection > section#helena > picture > img.bg-img `section.panel-collection > section#helena > picture > img.bg-img`	www.stanford.edu/wp-content/uploads/2025/10/20220510_Helena_Zhang_N6A1299.jpg
section#bottom-background > div.img-container > picture > img.bg-img `section#bottom-background > div.img-container > picture > img.bg-img`	www.stanford.edu/wp-content/uploads/2021/10/dish-andrew-sm-767x681.jpg
figure.landscape > a > picture > img `figure.landscape > a > picture > img`	www.stanford.edu/wp-content/uploads/2026/04/creators_JA1_0324-767x511.jpg
Three students work together in a robotics lab `section.highlight > figure.landscape > picture > img`	/wp-content/uploads/2023/05/20230418_Grayson_Armour_95A06...
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	/wp-content/uploads/2023/03/20220714Hopkins_Marine_Statio...
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	/wp-content/uploads/2023/03/20211117_Elizabeth_Reese_N6A0...
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	/wp-content/uploads/2025/10/20200212_Conservator_SRA6885-...
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	/wp-content/uploads/2025/10/20240826_Spirit_House_N6A3451...
An audience watches an orchestral performance in Bing Concert Hall `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2025/10/2012JG23.625RE-767x511.jpg
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2022/04/Health-care-1-767x511.jpg
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2022/04/Health-care-2-767x511.jpg
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2022/04/Health-care-3-767x511.jpg
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2022/04/Campus-life-1-767x481.jpg
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2025/10/ePluribus-767x481.jpg
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2022/04/Campus-life-3-767x481.jpg
Stanford Men's Gymnastics celebrates a third consecutive NCAA championship `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2022/04/Gym-champs-767x479.jpg
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2024/08/Ledecky2-767x479.png
section.highlight > figure.landscape > picture > img `section.highlight > figure.landscape > picture > img`	www.stanford.edu/wp-content/uploads/2022/04/Impact-767x479.jpg
Stanford student Maya Guzdar and friends walk through an archway on Main Quad `section#welcome-to-stanford > figure > picture > img`	www.stanford.edu/wp-content/uploads/2022/08/Maya-admission-767x460.jpg

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

●Layout shift culprits

●Document request latency

●Optimize DOM size

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●User Timing marks and measures 14 user timings

●Avoid long main-thread tasks 20 long tasks found

●Avoid non-composited animations 4 animated elements found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 140 ms

●Server Backend Latencies 330 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

●Avoid large layout shifts 1 layout shift found

○INP breakdown

○LCP request discovery

100

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.

○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.

●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

●`<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.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●Uses ARIA roles only on compatible elements

●Identical links have the same purpose.

○`[accesskey]` values are unique

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

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

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements with 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

○Form elements have associated labels

○Links are distinguishable without relying on color.

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

○`<object>` elements have alternate text

○Select elements have associated label elements.

○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.

○Image elements do not have `[alt]` attributes that are redundant text.

○Elements with visible text labels have matching accessible names.

○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.

○`<td>` elements in a large `<table>` have one or more table headers.

Best Practices

General

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	connect.facebook.net/en_US/fbevents.js line 273, col 769

●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

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Ensure proper origin isolation with COOP

○Mitigate clickjacking with XFO or CSP

SEO

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

Content Best Practices

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Link destination	Link Text
news.stanford.edu/features/research-at-stanford	Read more
news.stanford.edu/stories/2025/05/meet-khoi-young-graduate-profile	Read more
news.stanford.edu/stories/2022/06/meet-helena-zhang	Learn more

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

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`