C — https://www.ethz.ch | BeaverCheck Audit

Site Health

Score: 70 / 100

Based on 8 categories, 0 sections

How is this calculated?

The overall score is a weighted average of individual category scores. Categories with more impact on user experience and security carry more weight.

Performance 25%Security 25%Accessibility 15%SEO 10%Infrastructure 10%Compliance 8%Content 5%Sustainability 2%

Weights reflect general web best practices. Individual needs may differ.

Top Priorities (5)

Content-Security-Policy header is missing

Security › Security Headers

HSTS header is missing

Security › Security Headers

No Content-Security-Policy header found

Security › Content Security Policy

1 image-only link(s) without alt text

Accessibility › Link & Button Quality

2 image(s) missing alt attribute

Accessibility › Alt Text Quality

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Markdown

[![BeaverCheck](https://beavercheck.com/badge?url=https%3A%2F%2Fwww.ethz.ch)](https://beavercheck.com/results/a8d1b9be-2598-c3ad-5934-43ad43723435)

HTML

<a href="https://beavercheck.com/results/a8d1b9be-2598-c3ad-5934-43ad43723435"><img src="https://beavercheck.com/badge?url=https%3A%2F%2Fwww.ethz.ch" alt="BeaverCheck Score"></a>

Image URL

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Lighthouse Scores

Industry-standard audits powered by Google Lighthouse.

Performance

Accessibility

100

Best Practices

SEO

Core Web Vitals

Key metrics that affect user experience.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

8.79 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

12.38 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

2.05 s

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.192

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

8.79 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

13.90 s

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.

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

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

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

Request	Cache TTL	Transfer Size
ethz.ch/etc/designs/ethz/js/default.js	3600.0 s	960.1 KiB
ethz.ch/etc/designs/ethz/fonts/MaterialIcons-Outlined.woff2	3600.0 s	127.5 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/2/im...	604800.0 s	833.0 KiB
ethz.ch/etc/designs/ethz/css.css	3600.0 s	81.7 KiB
cdn.cookielaw.org/scripttemplates/202511.1.0/otBannerSdk.js	86400.0 s	124.4 KiB
ethz.ch/de/_jcr_content/homehero/imageLarge.imageformat.1632x918.708159214.jpg	604800.0 s	386.5 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/3/im...	604800.0 s	183.8 KiB
/de/_jcr_content/par/multitopicteaser/2/image.imageformat...	604800.0 s	126.9 KiB
/logos/f01260a5-58f2-42dc-8a16-b4efb17fd21d/018ec76d-f793...	86400.0 s	31.1 KiB
/de/_jcr_content/par/multitopicteaser_907/1/image.imagefo...	604800.0 s	113.0 KiB
/de/_jcr_content/par/multitopicteaser/1/image.imageformat...	604800.0 s	95.2 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/1/im...	604800.0 s	90.6 KiB
ethz.ch/de/_jcr_content/homehero/imageSmall.imageformat.489x489.707995886.jpg	604800.0 s	76.1 KiB
/de/news-und-veranstaltungen/eth-news/news/2026/03/globe-...	604800.0 s	62.2 KiB
/scripttemplates/otSDKStub.js?did=d4b64b56-c565-41a3-9aef...	86400.0 s	9.1 KiB
cdn.cookielaw.org/logos/static/poweredBy_cp_logo.svg	86400.0 s	2.6 KiB
ethz.ch/etc/designs/ethz/img/icons/svg/instagram-white.svg	3600.0 s	1.2 KiB
ethz.ch/etc/designs/ethz/img/icons/svg/tiktok-white.svg	3600.0 s	762 B
ethz.ch/etc/designs/ethz/img/icons/svg/youtube-white.svg	3600.0 s	548 B
ethz.ch/etc/designs/ethz/img/icons/svg/linkedin-white.svg	3600.0 s	525 B
ethz.ch/etc/designs/ethz/img/icons/svg/facebook-white.svg	3600.0 s	476 B
ethz.ch/etc/designs/ethz/img/icons/svg/rss-white.svg	3600.0 s	347 B

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]

items: [map[node:map[type:text value:Total] score:0.19224299999999997] map[node:map[boundingRect:map[bottom:11880 height:11756 left:0 right:412 top:124 width:412] lhId:page-1-SECTION nodeLabel:Direkt zum Inhalt springen ETH Zürich: Übersicht und Aktuelles ETH-Studierende … path:1,HTML,1,BODY,9,DIV,3,SECTION selector:body#eth-petrol > div.site-wrapper > section#content snippet:<section id="content" class="site-content" style="margin-top: calc(124px);"> type:node] score:0.178773] map[node:map[boundingRect:map[bottom:4412 height:1646 left:0 right:412 top:2766 width:412] lhId:page-3-DIV nodeLabel:An der ETH studieren Studienangebot Erfahren Sie, welcher Studiengang am best… path:1,HTML,1,BODY,9,DIV,3,SECTION,1,DIV,0,SECTION,4,DIV,0,DIV,1,SECTION,0,DIV selector:div.par > div.par > section.homepage-wide-section > div.multitopicteaser snippet:<div class="multitopicteaser basecomponent"> type:node] score:0.013366] map[node:map[boundingRect:map[bottom:117 height:37 left:319 right:410 top:81 width:91] lhId:page-5-DIV nodeLabel:de DE EN FR (TA) IT (TA) path:1,HTML,1,BODY,9,DIV,1,HEADER,3,DIV,0,DIV,3,DIV selector:header.site-header > div#navTopRoot > div.header__navbar > div.header__language snippet:<div class="header__language header__mobile-only"> type:node] score:0.000104]]

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

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.

URL	Est Savings
ethz.ch/bin/ethz/fonts/regular.woff2	180 ms
ethz.ch/bin/ethz/fonts/medium.woff2	180 ms
ethz.ch/bin/ethz/fonts/bold.woff2	105 ms
ethz.ch/etc/designs/ethz/fonts/MaterialIcons-Outlined.woff2	100 ms

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

lhId: page-0-IMG

nodeLabel: a > div.HomeHero > figure.HomeHero__media > img

path: 1,HTML,1,BODY,9,DIV,3,SECTION,1,DIV,0,SECTION,2,SECTION,0,DIV,0,DIV,1,DIV,0,A,0,DIV,2,FIGURE,0,IMG

selector: a > div.HomeHero > figure.HomeHero__media > img

snippet: <img src="/de/_jcr_content/homehero/imageSmall.imageformat.489x489.707995886.jpg">

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.

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.

URL	Transfer Size	Duration
ethz.ch/etc/designs/ethz/js/default.js	960.1 KiB	4.8 s
ethz.ch/etc/designs/ethz/css.css	81.7 KiB	454 ms

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

	URL	Resource Size	Est Savings
div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img `div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img`	/de/_jcr_content/par/multitopicteaser_cop_1437726188/2/im...	827.1 KiB	792.4 KiB
div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img `div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img`	/de/_jcr_content/par/multitopicteaser_cop_1437726188/3/im...	182.4 KiB	155.4 KiB
div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img `div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img`	/de/_jcr_content/par/multitopicteaser_cop_1437726188/1/im...	89.9 KiB	74.6 KiB
a > div.HomeHero > figure.HomeHero__media > img `a > div.HomeHero > figure.HomeHero__media > img`	ethz.ch/de/_jcr_content/homehero/imageSmall.imageformat.489x489.707995886.jpg	75.4 KiB	43.4 KiB
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyloaded `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyloaded`	/de/news-und-veranstaltungen/eth-news/news/2026/03/globe-...	61.7 KiB	26.4 KiB

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

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.

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

Estimated savings: 1.9 s

URL	Time Spent
www.ethz.ch/	1.0 s
ethz.ch/	852 ms
ethz.ch/de.html	0.0 ms

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS

Element	Layout shift score
Direkt zum Inhalt springen ETH Zürich: Übersicht und Aktuelles ETH-Studierende … `body#eth-petrol > div.site-wrapper > section#content`	0.179
An der ETH studieren Studienangebot Erfahren Sie, welcher Studiengang am best… `div.par > div.par > section.homepage-wide-section > div.multitopicteaser`	0.013
de DE EN FR (TA) IT (TA) `header.site-header > div#navTopRoot > div.header__navbar > div.header__language`	0.000

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.

TTI

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.

Estimated savings: 150 ms 97.5 KiB

URL	Transfer Size	Est Savings
ethz.ch/etc/designs/ethz/css.css	81.6 KiB	78.0 KiB
	22.0 KiB	19.5 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.

Estimated savings: 2.3 s 540.1 KiB

URL	Transfer Size	Est Savings
ethz.ch/etc/designs/ethz/js/default.js	958.0 KiB	405.5 KiB
www.googletagmanager.com/gtm.js?id=GTM-5KC3PX6	175.2 KiB	68.7 KiB
cdn.cookielaw.org/scripttemplates/202511.1.0/otBannerSdk.js	124.3 KiB	65.9 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.

URL	Total CPU Time	Script Evaluation	Script Parse
ethz.ch/etc/designs/ethz/js/default.js	2.2 s	1.4 s	546 ms
ethz.ch/de.html	863 ms	52 ms	5.4 ms
www.googletagmanager.com/gtm.js?id=GTM-5KC3PX6	593 ms	497 ms	82 ms
Unattributable	377 ms	11 ms	0.0 ms
cdn.cookielaw.org/scripttemplates/202511.1.0/otBannerSdk.js	293 ms	178 ms	60 ms
ethz.ch/etc/designs/ethz/css.css	64 ms	0.0 ms	0.0 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

Category	Time Spent
Script Evaluation	2.2 s
Other	764 ms
Script Parsing & Compilation	697 ms
Style & Layout	550 ms
Parse HTML & CSS	135 ms
Rendering	93 ms
Garbage Collection	23 ms

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

URL	Transfer Size
ethz.ch/etc/designs/ethz/js/default.js	960.1 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/2/im...	833.0 KiB
ethz.ch/de/_jcr_content/homehero/imageLarge.imageformat.1632x918.708159214.jpg	386.5 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/3/im...	183.8 KiB
www.googletagmanager.com/gtm.js?id=GTM-5KC3PX6	175.6 KiB
ethz.ch/etc/designs/ethz/fonts/MaterialIcons-Outlined.woff2	127.5 KiB
/de/_jcr_content/par/multitopicteaser/2/image.imageformat...	126.9 KiB
cdn.cookielaw.org/scripttemplates/202511.1.0/otBannerSdk.js	124.4 KiB
/de/_jcr_content/par/multitopicteaser_907/1/image.imagefo...	113.0 KiB
/de/_jcr_content/par/multitopicteaser/1/image.imageformat...	95.2 KiB

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

	URL
ETH Zürich - Homepage auf TikTok `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/tiktok-white.svg
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyloaded `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyloaded`	/de/news-und-veranstaltungen/eth-news/news/2026/03/globe-...
ETH Zürich - Homepage auf Instagram `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/instagram-white.svg
ETH Zürich - Homepage auf Facebook `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/facebook-white.svg
ETH Zürich - Homepage auf LinkedIn `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/linkedin-white.svg
Abonnieren Sie den Newsfeed des ETH Zürich - Homepage `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/rss-white.svg
ETH Zürich - Homepage auf YouTube `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/youtube-white.svg
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload`
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload`
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload`
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload`

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

●Optimize DOM size

●Forced reflow

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●Avoid long main-thread tasks 12 long tasks found

●Avoid non-composited animations 2 animated elements found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 80 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 90 ms

○INP breakdown

○User Timing marks and measures

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.

Failing Elements
a > div.HomeHero > figure.HomeHero__media > img `a > div.HomeHero > figure.HomeHero__media > img`

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Failing Elements
div#navTopRoot > div.header__navbar > div.header__search-link-container > a.header__search-link `div#navTopRoot > div.header__navbar > div.header__search-link-container > a.header__search-link`

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.

Failing Elements
ETH-Studierende entwickeln digitale Werkzeuge für die UNO chevron_right Den Art… `div.homehero > div.homehero__wrapper > div#homeHero > a`

○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.

●`[accesskey]` values are unique

●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 are distinguishable without relying on color.

●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

●Document has a main landmark.

●Deprecated ARIA roles were not used

○`button`, `link`, and `menuitem` elements 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

○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.

○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

General

Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. Learn more about source maps.

URL	Map URL
ethz.ch/etc/designs/ethz/js/default.js	ethz.ch/etc/designs/ethz/js/ally.min.js.map

●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

○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

Meta descriptions may be included in search results to concisely summarize page content. Learn more about the meta description.

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.

Failing Elements
a > div.HomeHero > figure.HomeHero__media > img `a > div.HomeHero > figure.HomeHero__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

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`

○robots.txt is valid

Lighthouse Scores

Industry-standard audits powered by Google Lighthouse. — Desktop

Performance

Accessibility

100

Best Practices

SEO

Core Web Vitals

Key metrics that affect user experience. — Desktop

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.86 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

2.65 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

225 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.702

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

2.73 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

2.65 s

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.

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

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

Request	Cache TTL	Transfer Size
ethz.ch/etc/designs/ethz/js/default.js	3600.0 s	960.1 KiB
ethz.ch/etc/designs/ethz/fonts/MaterialIcons-Outlined.woff2	3600.0 s	127.5 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/2/im...	604800.0 s	832.9 KiB
ethz.ch/etc/designs/ethz/css.css	3600.0 s	81.7 KiB
cdn.cookielaw.org/scripttemplates/202511.1.0/otBannerSdk.js	86400.0 s	124.4 KiB
ethz.ch/de/_jcr_content/homehero/imageLarge.imageformat.1632x918.708159214.jpg	604800.0 s	386.5 KiB
/de/news-und-veranstaltungen/eth-news/news/2026/03/proteo...	604800.0 s	340.8 KiB
/de/_jcr_content/par/multitopicteaser_907/3/image.imagefo...	604800.0 s	211.1 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/3/im...	604800.0 s	183.7 KiB
/de/_jcr_content/par/multitopicteaser_907_282583525/2/ima...	604800.0 s	129.5 KiB
/de/_jcr_content/par/multitopicteaser/2/image.imageformat...	604800.0 s	126.9 KiB
/logos/f01260a5-58f2-42dc-8a16-b4efb17fd21d/018ec76d-f793...	86400.0 s	31.2 KiB
/de/_jcr_content/par/multitopicteaser_907/1/image.imagefo...	604800.0 s	113.0 KiB
/de/_jcr_content/par/multitopicteaser/1/image.imageformat...	604800.0 s	95.1 KiB
/de/_jcr_content/par/multitopicteaser_907/2/image.imagefo...	604800.0 s	91.1 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/1/im...	604800.0 s	90.6 KiB
/de/news-und-veranstaltungen/eth-news/news/2026/03/globe-...	604800.0 s	82.7 KiB
/de/_jcr_content/par/multitopicteaser_907_282583525/1/ima...	604800.0 s	81.0 KiB
ethz.ch/de/_jcr_content/homehero/imageSmall.imageformat.489x489.707995886.jpg	604800.0 s	76.0 KiB
/de/_jcr_content/par/multitopicteaser_907_282583525/3/ima...	604800.0 s	74.8 KiB
/scripttemplates/otSDKStub.js?did=d4b64b56-c565-41a3-9aef...	86400.0 s	9.1 KiB
cdn.cookielaw.org/logos/static/poweredBy_cp_logo.svg	86400.0 s	2.5 KiB
ethz.ch/etc/designs/ethz/img/icons/svg/instagram-white.svg	3600.0 s	1.2 KiB
ethz.ch/etc/designs/ethz/img/icons/svg/tiktok-white.svg	3600.0 s	762 B
ethz.ch/etc/designs/ethz/img/icons/svg/youtube-white.svg	3600.0 s	548 B
ethz.ch/etc/designs/ethz/img/icons/svg/linkedin-white.svg	3600.0 s	525 B
ethz.ch/etc/designs/ethz/img/icons/svg/facebook-white.svg	3600.0 s	476 B
ethz.ch/etc/designs/ethz/img/icons/svg/rss-white.svg	3600.0 s	347 B

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

items: [map[node:map[type:text value:Total] score:0.702148] map[node:map[boundingRect:map[bottom:7274 height:7022 left:0 right:1350 top:252 width:1350] lhId:page-3-SECTION nodeLabel:Direkt zum Inhalt springen ETH Zürich: Übersicht und Aktuelles ETH-Studierende … path:1,HTML,1,BODY,9,DIV,3,SECTION selector:body#eth-petrol > div.site-wrapper > section#content snippet:<section id="content" class="site-content"> type:node] score:0.63825] map[node:map[boundingRect:map[bottom:1041 height:789 left:0 right:1350 top:252 width:1350] lhId:page-6-DIV nodeLabel:ETH-Studierende entwickeln digitale Werkzeuge für die UNO ETH-Studierende entwi… path:1,HTML,1,BODY,9,DIV,3,SECTION,1,DIV,0,SECTION,2,SECTION,0,DIV selector:div#contentContainer > section#contentMain > section.basecomponent > div.homehero snippet:<div class="homehero basecomponent"> type:node] score:0.063898]]

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

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.

URL	Est Savings
ethz.ch/bin/ethz/fonts/bold.woff2	185 ms
ethz.ch/bin/ethz/fonts/medium.woff2	185 ms
ethz.ch/bin/ethz/fonts/regular.woff2	180 ms
ethz.ch/etc/designs/ethz/fonts/MaterialIcons-Outlined.woff2	105 ms

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

	URL	Resource Size	Est Savings
div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img `div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img`	/de/_jcr_content/par/multitopicteaser_cop_1437726188/2/im...	827.1 KiB	815.3 KiB
a > div.HomeHero > figure.HomeHero__media > img `a > div.HomeHero > figure.HomeHero__media > img`	ethz.ch/de/_jcr_content/homehero/imageLarge.imageformat.1632x918.708159214.jpg	383.8 KiB	326.5 KiB
div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img `div.MultiTopicTeaser > figure.MultiTopicTeaser__media > div.MultiTopicTeaser__media-img-wrapper > img`	/de/_jcr_content/par/multitopicteaser_cop_1437726188/1/im...	89.9 KiB	84.7 KiB

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

lhId: page-1-IMG

nodeLabel: a > div.HomeHero > figure.HomeHero__media > img

path: 1,HTML,1,BODY,9,DIV,3,SECTION,1,DIV,0,SECTION,2,SECTION,0,DIV,0,DIV,1,DIV,0,A,0,DIV,1,FIGURE,0,IMG

selector: a > div.HomeHero > figure.HomeHero__media > img

snippet: <img src="/de/_jcr_content/homehero/imageLarge.imageformat.1632x918.708159214.jpg">

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.

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.

URL	Transfer Size	Duration
ethz.ch/etc/designs/ethz/js/default.js	960.1 KiB	752 ms
ethz.ch/etc/designs/ethz/css.css	81.7 KiB	84 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.

Estimated savings: 770 ms

URL	Time Spent
www.ethz.ch/	462 ms
ethz.ch/	308 ms
ethz.ch/de.html	0.0 ms

Element	Layout shift score
Direkt zum Inhalt springen ETH Zürich: Übersicht und Aktuelles ETH-Studierende … `body#eth-petrol > div.site-wrapper > section#content`	0.638
ETH-Studierende entwickeln digitale Werkzeuge für die UNO ETH-Studierende entwi… `div#contentContainer > section#contentMain > section.basecomponent > div.homehero`	0.064

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.

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.

TTI

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.

Estimated savings: 80 ms 95.2 KiB

URL	Transfer Size	Est Savings
ethz.ch/etc/designs/ethz/css.css	81.6 KiB	76.1 KiB
	22.0 KiB	19.2 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.

Estimated savings: 380 ms 540.8 KiB

URL	Transfer Size	Est Savings
ethz.ch/etc/designs/ethz/js/default.js	958.0 KiB	406.2 KiB
www.googletagmanager.com/gtm.js?id=GTM-5KC3PX6	175.2 KiB	68.7 KiB
cdn.cookielaw.org/scripttemplates/202511.1.0/otBannerSdk.js	124.3 KiB	65.9 KiB

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

URL	Transfer Size
ethz.ch/etc/designs/ethz/js/default.js	960.1 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/2/im...	832.9 KiB
ethz.ch/de/_jcr_content/homehero/imageLarge.imageformat.1632x918.708159214.jpg	386.5 KiB
/de/news-und-veranstaltungen/eth-news/news/2026/03/proteo...	340.8 KiB
/de/_jcr_content/par/multitopicteaser_907/3/image.imagefo...	211.1 KiB
/de/_jcr_content/par/multitopicteaser_cop_1437726188/3/im...	183.7 KiB
www.googletagmanager.com/gtm.js?id=GTM-5KC3PX6	175.6 KiB
/de/_jcr_content/par/multitopicteaser_907_282583525/2/ima...	129.5 KiB
ethz.ch/etc/designs/ethz/fonts/MaterialIcons-Outlined.woff2	127.5 KiB
/de/_jcr_content/par/multitopicteaser/2/image.imageformat...	126.9 KiB

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

	URL
ETH Zürich - Homepage auf TikTok `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/tiktok-white.svg
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyloaded `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyloaded`	/de/news-und-veranstaltungen/eth-news/news/2026/03/proteo...
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyloaded `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyloaded`	/de/news-und-veranstaltungen/eth-news/news/2026/03/globe-...
ETH Zürich - Homepage auf Instagram `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/instagram-white.svg
ETH Zürich - Homepage auf Facebook `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/facebook-white.svg
ETH Zürich - Homepage auf LinkedIn `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/linkedin-white.svg
Abonnieren Sie den Newsfeed des ETH Zürich - Homepage `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/rss-white.svg
ETH Zürich - Homepage auf YouTube `ul.social-icons > li > a.social-icon > img`	ethz.ch/etc/designs/ethz/img/icons/svg/youtube-white.svg
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload`
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload`
div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload `div.Teaser__wrapper > a > picture.ResponsiveImage > img.lazyload`

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

●Optimize DOM size

●Forced reflow

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●JavaScript execution time 0.8 s

●Minimizes main-thread work 1.4 s

●Avoid long main-thread tasks 4 long tasks found

●Avoid non-composited animations 2 animated elements found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 90 ms

●Server Backend Latencies 120 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 90 ms

○INP breakdown

○User Timing marks and measures

Accessibility

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.

Failing Elements
a > div.HomeHero > figure.HomeHero__media > img `a > div.HomeHero > figure.HomeHero__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.

Failing Elements
ETH-Studierende entwickeln digitale Werkzeuge für die UNO chevron_right Den Art… `div.homehero > div.homehero__wrapper > div#homeHero > a`

○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.

●`[accesskey]` values are unique

●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 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

●Touch targets have sufficient size and spacing.

●Heading elements appear in a sequentially-descending order

●Document has a main landmark.

●Deprecated ARIA roles were not used

○`button`, `link`, and `menuitem` elements 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

○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.

○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

General

URL	Map URL
ethz.ch/etc/designs/ethz/js/default.js	ethz.ch/etc/designs/ethz/js/ally.min.js.map

●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

○Redirects HTTP traffic to HTTPS

○Mitigate clickjacking with XFO or CSP

SEO

Content Best Practices

Meta descriptions may be included in search results to concisely summarize page content. Learn more about the meta description.

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.

Failing Elements
a > div.HomeHero > figure.HomeHero__media > img `a > div.HomeHero > figure.HomeHero__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

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`

○robots.txt is valid

Browse & Analyze

Learn

Results for https://www.ethz.ch

Site Health

Top Priorities (5)

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Names and labels

Best Practices

General

SEO

Content Best Practices

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Names and labels

Best Practices

General

SEO

Content Best Practices

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