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

Audit breakdown by category with detailed findings.

71

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.

RequestCache TTLTransfer Size
www.bu.edu/home/img/26-1132-YANG-003_crop-1500x1032.jpg1800.0 s294.9 KiB
www.bu.edu/home/css/style.min_1.css1800.0 s151.8 KiB
www.bu.edu/home/img/crop-25-1404-JOBCAPE-165-1024x684.jpg1800.0 s120.8 KiB
www.bu.edu/home/img/crop-26-1024-CAMED-109-1024x684.jpg1800.0 s99.6 KiB
www.bu.edu/home/img/Johar-Speaking-feat-1024x684.jpg1800.0 s69.1 KiB
www.bu.edu/home/font/WhitneySSmAdvancedSemibold_normal_normal.woff21800.0 s65.3 KiB
www.bu.edu/home/font/WhitneySSmAdvancedBook_normal_normal.woff21800.0 s63.6 KiB
www.bu.edu/home/font/TiemposHeadline-Regular-Italic.woff1800.0 s51.0 KiB
www.bu.edu/home/font/TiemposHeadline-Medium-Italic.woff1800.0 s49.7 KiB
www.bu.edu/home/font/TiemposHeadline-Bold-Italic.woff1800.0 s49.7 KiB
www.bu.edu/home/font/TiemposHeadline-Regular.woff1800.0 s49.2 KiB
www.bu.edu/home/font/TiemposHeadline-Bold.woff1800.0 s47.9 KiB
www.bu.edu/home/font/d4a4a960-2cf2-430e-8b13-cbf6f261ddb9-3.woff1800.0 s36.9 KiB
www.bu.edu/home/font/8e221891-e89b-4eae-95ca-6346d9a41d20-3.woff1800.0 s36.8 KiB
www.bu.edu/home/font/019c3a13-b3d7-4c5a-be27-07a8334a43e6-3.woff1800.0 s36.8 KiB
www.bu.edu/home/js/jquery.min.js1800.0 s30.9 KiB
www.bu.edu/home/font/bu-default-icons.woff1800.0 s29.5 KiB
www.bu.edu/home/img/icon-buhp-rhett.png1800.0 s26.0 KiB
www.bu.edu/wp-includes/js/wp-emoji-release.min.js?ver=5.8.100.0 ms18.8 KiB
www.bu.edu/home/js/bu-prepress-frontend.js1800.0 s21.5 KiB
www.bu.edu/home/img/26-1225-CAMPUS-017-feat-150x150.jpg1800.0 s14.2 KiB
www.bu.edu/home/img/All-NVC-Winners-feat-150x150.jpg1800.0 s12.9 KiB
www.bu.edu/home/img/crop-26-1228-KAHN-090-150x150.jpg1800.0 s12.4 KiB
www.bu.edu/home/js/bu-blocks-frontend.js1800.0 s11.1 KiB
www.bu.edu/home/js/modernizr.js1800.0 s11.0 KiB
www.bu.edu/home/css/style.min.css1800.0 s10.9 KiB
www.bu.edu/home/js/popper.min.js1800.0 s7.9 KiB
www.bu.edu/home/js/script.js1800.0 s6.2 KiB
www.bu.edu/home/css/custom.min.css1800.0 s4.8 KiB
www.bu.edu/home/js/jquery-migrate.min.js1800.0 s4.7 KiB
www.bu.edu/home/img/masterplate112x50.png1800.0 s4.2 KiB
www.bu.edu/home/js/micromodal.min.js1800.0 s3.4 KiB
www.bu.edu/home/js/jquery.waypoints-4.0.0.min.js1800.0 s3.3 KiB
www.bu.edu/home/js/tooltip.min.js1800.0 s2.8 KiB
www.bu.edu/home/css/bu-slideshow.css1800.0 s2.5 KiB
www.bu.edu/home/css/bu-banners.min.css1800.0 s2.2 KiB
www.bu.edu/home/css/zotpress.shortcode.min.css1800.0 s1.9 KiB
www.bu.edu/home/js/analytics-talk-content-tracking.js1800.0 s1.8 KiB
www.bu.edu/home/css/alert.css1800.0 s1.5 KiB
www.bu.edu/home/js/screenfull.min.js1800.0 s1.4 KiB
www.bu.edu/home/img/icon-buhp-giving.svg1800.0 s1.4 KiB
www.bu.edu/home/js/wp-embed.min.js1800.0 s1.4 KiB
www.bu.edu/home/img/icon-buhp-todayevents.svg1800.0 s1.2 KiB
www.bu.edu/home/img/icon-buhp-hub.svg1800.0 s1.1 KiB
www.bu.edu/home/css/fonts.css1800.0 s934 B
cdn.fonts.net/t/1.css?apiType=css&projectid=b6ad2f95-8b9c-41ce-8e24-66c08ae7befb1.0 s639 B
www.bu.edu/home/css/block-frontend.css1800.0 s616 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.

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.

URLEst Savings
www.bu.edu/home/font/bu-default-icons.woff25 ms
www.bu.edu/home/font/TiemposHeadline-Medium-Italic.woff15 ms
www.bu.edu/home/font/TiemposHeadline-Bold.woff15 ms
www.bu.edu/home/font/TiemposHeadline-Regular-Italic.woff15 ms
www.bu.edu/home/font/TiemposHeadline-Bold-Italic.woff15 ms
www.bu.edu/home/font/019c3a13-b3d7-4c5a-be27-07a8334a43e6-3.woff10 ms
www.bu.edu/home/font/8e221891-e89b-4eae-95ca-6346d9a41d20-3.woff10 ms
www.bu.edu/home/font/d4a4a960-2cf2-430e-8b13-cbf6f261ddb9-3.woff5.0 ms
www.bu.edu/home/font/TiemposHeadline-Regular.woff5.0 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:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:26.03 source:map[column:5949 line:0 type:source-location url:https://www.bu.edu/home/js/modernizr.js urlProvider:network]] map[reflowTime:5.444 source:map[column:11329 line:0 type:source-location url:https://www.bu.edu/home/js/modernizr.js urlProvider:network]] map[reflowTime:128.898 source:map[type:text value:[unattributed]]]]

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
div.bu-banner > div.bu-banner-media > picture.bu-banner-img > img.bu-banner-img div.bu-banner > div.bu-banner-media > picture.bu-banner-img > img.bu-banner-img
www.bu.edu/home/img/26-1132-YANG-003_crop-1500x1032.jpg294.4 KiB126.2 KiB
Photo: Falmouth, MassachusettsEmmanuelle Bogomolni (CAS’26), Guest Student at t… section.buhp-homepage-article-container > div.buhp-homepage-article > figure.buhp-homepage-article-media > img.attachment-large
www.bu.edu/home/img/crop-25-1404-JOBCAPE-165-1024x684.jpg120.3 KiB67.4 KiB
Photo: Papadakis explains that her doctors could rule out cystic fibrosis becau… section.buhp-homepage-article-container > div.buhp-homepage-article > figure.buhp-homepage-article-media > img.attachment-large
www.bu.edu/home/img/crop-26-1024-CAMED-109-1024x684.jpg99.1 KiB52.2 KiB
Photo: BU alum Johar Singh talking in front of a crowd in a blue quarter zip sh… section.buhp-homepage-article-container > div.buhp-homepage-article > figure.buhp-homepage-article-media > img.attachment-large
www.bu.edu/home/img/Johar-Speaking-feat-1024x684.jpg68.6 KiB36.2 KiB
li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img
www.bu.edu/home/img/icon-buhp-rhett.png25.5 KiB24.8 KiB
Photo: MBTA Green Line train in Boston going down Commonwealth Ave li.buhp-homepage-headlines-item > div.buhp-homepage-headlines-media-container > figure.buhp-homepage-headlines-media > img.attachment-thumbnail
www.bu.edu/home/img/26-1225-CAMPUS-017-feat-150x150.jpg13.7 KiB10.1 KiB
Photo: New Venture Competition winners pose onstage at Boston University’s Inno… li.buhp-homepage-headlines-item > div.buhp-homepage-headlines-media-container > figure.buhp-homepage-headlines-media > img.attachment-thumbnail
www.bu.edu/home/img/All-NVC-Winners-feat-150x150.jpg12.4 KiB8.8 KiB
Photo: College student sitting for portrait at a piano li.buhp-homepage-headlines-item > div.buhp-homepage-headlines-media-container > figure.buhp-homepage-headlines-media > img.attachment-thumbnail
www.bu.edu/home/img/crop-26-1228-KAHN-090-150x150.jpg11.9 KiB8.3 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-0-IMG
nodeLabel: div.bu-banner > div.bu-banner-media > picture.bu-banner-img > img.bu-banner-img
path: 6,HTML,2,BODY,0,DIV,3,MAIN,0,SECTION,0,DIV,0,DIV,0,PICTURE,6,IMG
selector: div.bu-banner > div.bu-banner-media > picture.bu-banner-img > img.bu-banner-img
snippet: <img width="1200" height="826" src="https://www.bu.edu/home/img/26-1132-YANG-003_crop-1500x1032.jpg" class="bu-banner-img" alt="" loading="lazy">

HTTP/2 and HTTP/3 offer many benefits over HTTP/1.1, such as multiplexing. Learn more about using modern HTTP.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLProtocol
www.bu.edu/http/1.1
www.bu.edu/home/css/alert.csshttp/1.1
www.bu.edu/home/css/style.min.csshttp/1.1
www.bu.edu/home/css/block-frontend.csshttp/1.1
www.bu.edu/home/css/bu-slideshow.csshttp/1.1
www.bu.edu/home/css/bu-banners.min.csshttp/1.1
www.bu.edu/home/css/style.min_1.csshttp/1.1
www.bu.edu/home/css/fonts.csshttp/1.1
www.bu.edu/home/css/zotpress.shortcode.min.csshttp/1.1
www.bu.edu/home/js/jquery.min.jshttp/1.1
www.bu.edu/home/js/jquery-migrate.min.jshttp/1.1
www.bu.edu/home/js/analytics-talk-content-tracking.jshttp/1.1
www.bu.edu/home/js/modernizr.jshttp/1.1
www.bu.edu/home/css/custom.min.csshttp/1.1
www.bu.edu/home/img/icon-buhp-rhett.pnghttp/1.1
www.bu.edu/home/img/icon-buhp-hub.svghttp/1.1
www.bu.edu/home/img/icon-buhp-giving.svghttp/1.1
www.bu.edu/home/js/bu-blocks-frontend.jshttp/1.1
www.bu.edu/home/js/jquery.waypoints-4.0.0.min.jshttp/1.1
www.bu.edu/home/js/popper.min.jshttp/1.1
www.bu.edu/home/js/tooltip.min.jshttp/1.1
www.bu.edu/home/js/micromodal.min.jshttp/1.1
www.bu.edu/home/js/screenfull.min.jshttp/1.1
www.bu.edu/home/js/bu-prepress-frontend.jshttp/1.1
www.bu.edu/home/js/script.jshttp/1.1
www.bu.edu/home/js/wp-embed.min.jshttp/1.1
www.bu.edu/wp-includes/js/wp-emoji-release.min.js?ver=5.8.10http/1.1
www.bu.edu/home/img/icon-buhp-todayevents.svghttp/1.1
www.bu.edu/home/img/masterplate112x50.pnghttp/1.1
www.bu.edu/home/font/bu-default-icons.woffhttp/1.1
www.bu.edu/home/font/d4a4a960-2cf2-430e-8b13-cbf6f261ddb9-3.woffhttp/1.1
www.bu.edu/home/font/019c3a13-b3d7-4c5a-be27-07a8334a43e6-3.woffhttp/1.1
www.bu.edu/home/font/TiemposHeadline-Medium-Italic.woffhttp/1.1
www.bu.edu/home/font/TiemposHeadline-Bold.woffhttp/1.1
www.bu.edu/home/font/TiemposHeadline-Regular-Italic.woffhttp/1.1
www.bu.edu/home/font/TiemposHeadline-Bold-Italic.woffhttp/1.1
www.bu.edu/home/font/8e221891-e89b-4eae-95ca-6346d9a41d20-3.woffhttp/1.1
www.bu.edu/home/font/WhitneySSmAdvancedSemibold_normal_normal.woff2http/1.1
www.bu.edu/home/font/WhitneySSmAdvancedBook_normal_normal.woff2http/1.1
www.bu.edu/home/font/TiemposHeadline-Regular.woffhttp/1.1
www.bu.edu/home/img/26-1132-YANG-003_crop-1500x1032.jpghttp/1.1
www.bu.edu/home/img/crop-26-1228-KAHN-090-150x150.jpghttp/1.1
www.bu.edu/home/img/All-NVC-Winners-feat-150x150.jpghttp/1.1
www.bu.edu/home/img/26-1225-CAMPUS-017-feat-150x150.jpghttp/1.1
www.bu.edu/home/img/crop-25-1404-JOBCAPE-165-1024x684.jpghttp/1.1
www.bu.edu/home/img/Johar-Speaking-feat-1024x684.jpghttp/1.1
www.bu.edu/home/img/crop-26-1024-CAMED-109-1024x684.jpghttp/1.1
www.bu.edu/favicon.icohttp/1.1

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.

URLTransfer SizeDuration
www.bu.edu/home/js/modernizr.js11.0 KiB89 ms
www.bu.edu/home/js/analytics-talk-content-tracking.js1.8 KiB
www.bu.edu/home/js/jquery-migrate.min.js4.7 KiB
www.bu.edu/home/js/jquery.min.js30.9 KiB171 ms
www.bu.edu/home/css/style.min_1.css151.8 KiB458 ms
www.bu.edu/home/css/alert.css1.5 KiB
www.bu.edu/home/css/fonts.css934 B
www.bu.edu/home/css/custom.min.css4.8 KiB
www.bu.edu/home/css/zotpress.shortcode.min.css1.9 KiB
www.bu.edu/home/css/style.min.css10.9 KiB171 ms
www.bu.edu/home/css/bu-slideshow.css2.5 KiB130 ms
www.bu.edu/home/css/bu-banners.min.css2.2 KiB130 ms
www.bu.edu/home/css/block-frontend.css616 B130 ms
cdn.fonts.net/t/1.css?apiType=css&projectid=b6ad2f95-8b9c-41ce-8e24-66c08ae7befb639 B229 ms

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: 649 ms
URLTime Spent
bu.edu/649 ms
www.bu.edu/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

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: 40 ms 14.4 KiB
URLTransfer SizeEst Savings
www.bu.edu/home/js/bu-prepress-frontend.js21.0 KiB10.0 KiB
www.bu.edu/home/js/bu-blocks-frontend.js10.6 KiB4.4 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: 120 ms 151.7 KiB
URLTransfer SizeEst Savings
www.bu.edu/home/css/style.min_1.css151.3 KiB141.4 KiB
www.bu.edu/home/css/style.min.css10.3 KiB10.3 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: 200 ms 264.8 KiB
URLTransfer SizeEst Savings
www.googletagmanager.com/gtag/js?id=G-ZLH6JNFYKK&cx=c&gtm=4e64h1156.9 KiB67.7 KiB
www.googletagmanager.com/gtag/js?id=G-HVBYYX9KF6&cx=c&gtm=4e64h1153.1 KiB65.4 KiB
www.googletagmanager.com/gtag/js?id=G-0Z1EBE5RV7157.1 KiB63.8 KiB
www.googletagmanager.com/gtm.js?id=GTM-WRNV87799.3 KiB47.7 KiB
www.bu.edu/home/js/jquery.min.js30.3 KiB20.2 KiB

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

●Max Potential First Input Delay 120 ms
●Layout shift culprits
●Optimize DOM size
●LCP breakdown
●Optimize viewport for mobile
●Minify CSS
●Avoids enormous network payloads Total size was 2,254 KiB
●User Timing marks and measures 15 user timings
●JavaScript execution time 0.7 s
●Minimizes main-thread work 1.3 s
●Avoid long main-thread tasks 7 long tasks found
●Image elements have explicit `width` and `height`
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 150 ms
●Server Backend Latencies 100 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 450 ms
●Avoid large layout shifts 2 layout shifts found
○INP breakdown
○Avoid non-composited animations
86

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.

ARIA

Focusable descendents within an `[aria-hidden="true"]` element prevent those interactive elements from being available to users of assistive technologies like screen readers. Learn how `aria-hidden` affects focusable elements.

Why this matters

Informational: a Permissions-Policy directive showing feature -> allowed origins.

Source: MDN Permissions-Policy

Failing Elements
CLOSE MENU Search Boston University... Admissions Undergraduate Graduate Intern… body#top > div.page-wrapper > div#buhp-navigation-modal

These are opportunities to improve the usage of ARIA in your application which may enhance the experience for users of assistive technology, like a screen reader.

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
GIVING nav.buhp-masthead-additional > ul.buhp-masthead-additional-list > li.buhp-masthead-additional-item > a
headlines: div.buhp-homepage-headlines > div.buhp-homepage-headlines-header > div.buhp-homepage-headlines-date > span
Resources for: div.page-wrapper > footer.site-footer > nav.utility-nav > h6.buhp-resources-header

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
Resources for: main#main > div#post-451587 > nav.utility-nav > h6.buhp-resources-header
Resources for: div.page-wrapper > footer.site-footer > nav.utility-nav > h6.buhp-resources-header

These are opportunities to improve keyboard navigation in your application.

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
li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img
li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img
li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > 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.

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
FULL MENU div.page-wrapper > header.buhp-masthead > nav.buhp-nav-condensed > button.nav-toggle
○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.
●ARIA attributes are used as specified for the element's role
●Elements use only permitted ARIA attributes
●Document has a `<title>` element
●`<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.
●Skip links are focusable.
●Document has a main landmark.
●Deprecated ARIA roles were not used
○`[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
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○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.
○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 clickjacking with XFO or CSP
●Mitigate DOM-based XSS with Trusted Types
●Detected JavaScript libraries
●Page has valid source maps
○Redirects HTTP traffic to HTTPS
85

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.bu.edu/articles/2026/retinal-prosthesis-age-related-macular-degeneration/Learn more

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
li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img
li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img
li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > img li.buhp-footer-cards-item > div.buhp-footer-cards-content > figure.buhp-footer-cards-item-media > 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 are crawlable
●robots.txt is valid
●Document has a valid `hreflang`
●Document has a valid `rel=canonical`

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