C — https://polimi.it | BeaverCheck Audit

Site Health

Score: 70 / 100

Based on 8 categories, 0 sections

Decent speed, but optimizing further could improve engagement.

Several missing protections leave your users and data exposed.

Several issues make your site difficult for assistive technology users.

Well-optimized for search — your content is discoverable.

Good server performance with room for optimization.

Mostly compliant — a few items need attention.

Good content signals with minor gaps.

Heavier than average — reducing page weight saves energy and bandwidth.

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.

How the composite score is calculated

How you compare

TYPO3 CMS · 23 peers

You 70

Avg 75

At average

0 50 100

Better than 4% of TYPO3 CMS sites See full TYPO3 CMS benchmark →

Bootstrap · 621 peers

You 70

Avg 73

At average

0 50 100

Better than 10% of Bootstrap sites See full Bootstrap benchmark →

Top Priorities (5)

Content-Security-Policy header is missing

Security gaps expose your site and users to attacks, eroding trust.

Security › Security Headers

No Content-Security-Policy header found

Security gaps expose your site and users to attacks, eroding trust.

Security › Content Security Policy

Page weighs 45.2 MB (41.9 MB transferred)

Performance issues directly impact user engagement and conversion rates.

Performance › Page Weight Budget

1 button(s) with no accessible text

Accessibility issues exclude users with disabilities — up to 15% of your potential audience.

Accessibility › Link & Button Quality

14 link(s) with no accessible text

Accessibility issues exclude users with disabilities — up to 15% of your potential audience.

Accessibility › Link & Button Quality

View fix priority matrix

Fix Priority Matrix

5 findings

Impact

Quick Wins

High impact, low effort — start here.

Strategic

High impact, requires investment.

Easy Improvements

Small gains, minimal effort.

Nothing in this quadrant — good news.

Deprioritize

Low impact, high effort — do last.

Nothing in this quadrant — good news.

← Low effort High effort →

Embed this badge

Markdown

[![BeaverCheck](https://beavercheck.com/badge?url=https%3A%2F%2Fpolimi.it)](https://beavercheck.com/results/f3c82807-0ce5-43bd-8381-1e6dc453c815)

HTML

<a href="https://beavercheck.com/results/f3c82807-0ce5-43bd-8381-1e6dc453c815"><img src="https://beavercheck.com/badge?url=https%3A%2F%2Fpolimi.it" alt="BeaverCheck Score"></a>

Image URL

https://beavercheck.com/badge?url=https%3A%2F%2Fpolimi.it

This badge auto-updates with your latest scan result.

What fixing these means

Your site performs reasonably well, but a few targeted fixes could meaningfully improve results. Your LCP of 13.6s exceeds Google's 2.5s 'Good' threshold and the 1 performance issue below directly contributes to it. Accessibility issues exclude users who rely on assistive technology — an estimated 15% of your potential audience. Addressing the critical issues below would have the most immediate impact on your user trust.

2 security gaps detected — browsers may warn visitors about your site.

Your LCP is 13.6s — fixing the 1 performance critical could bring it under Google's 2.5s 'Good' threshold.

2 accessibility issues exclude users who rely on assistive technology.

Conversion Barriers

2 critical 4 warning

6 barrier(s) likely increasing bounce by ~26%.

Speed (2)

Page takes 13.6s to load

+12% bounce

Users abandon at ~3s — you're 11.1s over the 2.5s threshold

Fix: Optimize render-blocking resources, preload the hero image, and compress images

High main-thread blocking time

+2% bounce

Page is non-interactive for 502ms after first paint

Fix: Defer third-party scripts and split large bundles

Trust (2)

No HSTS header

+1% bounce

Returning visitors are briefly exposed to downgrade attacks on first request

Fix: Set Strict-Transport-Security: max-age=31536000; includeSubDomains

No Content-Security-Policy header

+1% bounce

Higher XSS blast radius — one compromised script can exfiltrate the checkout form

Fix: Ship a reporting-only CSP first, then enforce once violations are clean

Navigation (2)

14 link(s) with generic text ("click here", "read more")

+1% bounce

Screen-reader users navigating by link list see no context — and search engines can't infer relevance

Fix: Rewrite with descriptive phrases that identify the destination

6 broken link(s) on the page

+5% bounce

Clicks land on 404s — trust drops and the session often ends

Fix: Fix or remove the broken destinations surfaced on the Content tab

Preliminary CRO audit — each barrier links to the tab with detailed analysis.

Return on Investment

€330 investment → €1,159/month returns + EUR 120,500,000 risk avoided

Payback period: < 1 month First-year ROI: +4115%

Investment

€330

6h · 5 findings

Monthly returns

€1,159 /mo

~€13,909 / year

Conversions recovered €1,149
Bandwidth savings €9.76

Regulatory risk avoided

EUR 120,500,000

if kept compliant

ePrivacy Directive EUR 100,000,000
GDPR EUR 20,000,000
EAA EUR 500,000

Payback period

0 12mo 24mo

€55 — in quick wins — start here for the fastest payback

Figures combine localized regulatory fine ceilings, search/conversion value priced against local CPC, and bandwidth waste estimates. Results depend on implementation quality and audience composition. Not legal or financial advice.

Full methodology & sources

Estimated Remediation Cost

€330

6.0 developer hours at €55/hr

Based on Italy rates (€55/hr)

Quick wins

€55 2 fixes in ~60 minutes

Start here for the best return on investment

Cost by category

Cost by effort level

Adjust assumptions

Custom rate

€ /hr

Rates reflect fully-loaded developer cost including overhead

How developer rates are sourced

What Inaction Is Costing You

€10,041,676 / month at risk

~€120,500,117 / year if left unfixed

Compliance Risk

€120,500,000

ePrivacy DirectiveGDPREAA

No privacy policy link detected
GDPR: EUR 10,000 – EUR 20,000,000
Trackers detected but no cookie policy found
GDPR: EUR 5,000 – EUR 10,000,000
Trackers detected but no cookie policy found
GDPR: EUR 10,000 – EUR 20,000,000

+44 more

Bandwidth Waste

€9.76 /mo

131816.0 MB/mo × 0.074 EUR/GB

Optimize transfer: save ~13.2 MB per page load
Saves €9.76/mo

Compliance figures represent the statutory maximum fine for the most severe triggered category, capped per regulation — not the sum of per-finding penalties. Based on published regulatory fine ranges. This is not legal advice.

Compliance methodology · SEO assumptions · Bandwidth model

Your performance is already good — improvements may show diminishing returns

Monthly visitors

Unique monthly visitors from your analytics

Conversion rate (%)

Purchases, signups, or key actions

Avg. order value

Optional — for revenue estimation

additional conversions/month

more engaged visitors from reduced bounce

potential monthly revenue

Current bounce (est.)

After fixes (est.)

Estimated bounce reduction

Fix 5 critical issues to capture this value

How this is calculated

Based on Google/Deloitte research ("Milliseconds Make Millions") showing a ~7% bounce rate increase per additional second of LCP above the 2.5s "Good" threshold.

Your site's LCP: → estimated after fixes.

These are estimates based on industry research — actual results vary

Bounce-rate model & assumptions

Your data stays in your browser — nothing is sent to our servers

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Lighthouse Scores

Industry-standard audits powered by Google Lighthouse.

Performance

Accessibility

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.

4.51 s

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

13.64 s

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

502 ms

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

0.000

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

5.35 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.

14.03 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.

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

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more ▾

Most users today run browsers that natively support ES6+, async/await, optional chaining, and the rest of modern JavaScript. Transpiling to ES5 'just in case' adds 20-40% to your bundle for no benefit. Configure your build to target a modern browserslist, or ship a differential bundle pair (modern + legacy) with the module/nomodule pattern.

Source: Google web.dev / Lighthouse

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.

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.

URL	Est Savings
/_assets/4b51f00386267395f41e0940abbcd656/Css/fonts/icomo...	405 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:4.683 source:map[column:72337 line:13 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js 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:2.535 source:map[column:4766 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:0.549 source:map[column:56906 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:9.237 source:map[column:10640 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:15.002 source:map[type:text value:[unattributed]]] map[reflowTime:4.007 source:map[column:48353 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:0.047 source:map[column:22 line:269 type:source-location url:https://www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/polimi.js?1775796139 urlProvider:network]] map[reflowTime:0.889 source:map[column:31 line:444 type:source-location url:https://www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/polimi.js?1775796139 urlProvider:network]] map[reflowTime:0.972 source:map[column:180407 line:0 type:source-location url:https://www.polimi.it/_assets/f34691673face4b5c642d176b42916a9/Library/klaro/klaro.js?1765201540 urlProvider:network]]]

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
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/2026/summer_hp.png	2.7 MiB	2.7 MiB
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/2026/Deploy.png	2.7 MiB	2.7 MiB
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/rettorato/Rettorato_1920x816_v03.jpg	1.5 MiB	1.4 MiB
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/2026/Firma_Polimi-_Autodromo_Monza.jpg	295.8 KiB	263.2 KiB
Eventi 22 aprile 2026 Convegni Convegno Renewable Energy 2026 Leggi 22 apr… `main#page-content > div.section > div.news > div.section--event`	www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Images/bgEvents.png	234.7 KiB	120.8 KiB
Build the Future! Scopri il nostro Open Day 2026 Futuri studenti `main#page-content > div.section > div#c18788 > div.banner-cta`	www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Images/borealis.jpg	415.6 KiB	78.1 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/b/7/csm_047-Hero_Sviluppo_Sostenib...	154.7 KiB	77.2 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/7/d/csm_PolimiSpringGames-200424-9...	138.8 KiB	61.3 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/d/3/csm_Card_il_Primo_politecnico_...	93.2 KiB	52.8 KiB
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-enhance-logo.png	32.6 KiB	31.1 KiB
Unitech International `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/Logo_Unitech.png	30.3 KiB	27.2 KiB
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-time-logo.png	26.6 KiB	24.4 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	www.polimi.it/fileadmin/_processed_/f/1/csm_test-04_800x600_4f8e0cc7d4.jpg	68.4 KiB	17.1 KiB
Ranking internazionali Un’eccellenza in Italia e nel mondo 1° In Italia 98° … `div.container > div.row > div.col-12 > div.card`	/_assets/4b51f00386267395f41e0940abbcd656/Images/card-gfx...	30.3 KiB	16.8 KiB
div.row > div.col-12 > div.card > ::after `div.row > div.col-12 > div.card > ::after`	/_assets/4b51f00386267395f41e0940abbcd656/Images/card-gfx...	27.5 KiB	14.0 KiB
Collaborazioni Partnership internazionali Orgogliosamente parte di una rete i… `main#page-content > div.section > div#c771 > div.banner-logos`	/_assets/4b51f00386267395f41e0940abbcd656/Images/banner-l...	27.5 KiB	13.2 KiB
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/IDEA_League.png	15.1 KiB	12.9 KiB
div.frame-group-container > div.frame-group-inner > div.frame-backgroundimage-container > div#frame-backgroundimage-c22291 `div.frame-group-container > div.frame-group-inner > div.frame-backgroundimage-container > div#frame-backgroundimage-c22291`	www.polimi.it/fileadmin/_processed_/d/3/csm_banner-cta-background_2a69104123.png	13.5 KiB	9.1 KiB
div#c14813 > div.hero > div.hero__background-image > img#cover-0 `div#c14813 > div.hero > div.hero__background-image > img#cover-0`	www.polimi.it/fileadmin/asset/video/covers/0_technology.jpg	60.9 KiB	6.7 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-18-IMG

nodeLabel: div#c14813 > div.hero > div.hero__background-image > img#cover-0

path: 1,HTML,1,BODY,4,DIV,4,MAIN,1,DIV,0,DIV,2,DIV,4,IMG

selector: div#c14813 > div.hero > div.hero__background-image > img#cover-0

snippet: <img id="cover-0" class="hero__background-image cover current" data-index="0" src="/fileadmin/asset/video/covers/0_technology.jpg" width="1920" height="1080" alt="" style="display: block;">

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

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
/typo3temp/assets/bootstrappackage/css/theme-8ec6393bb66a...	50.1 KiB	1.2 s
www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Css/polimi.css?1775796139	40.2 KiB	611 ms
/_assets/f34691673face4b5c642d176b42916a9/Stylesheet/styl...	5.7 KiB
www.polimi.it/_assets/95f1fea155c1725894ea138b1edbb31d/Scss/corsi.css?1775043311	489 B
/typo3temp/assets/css/e7e212200e72edb6153da3c9aedf7517.cs...	582 B
/_assets/f6ef6adaf5c92bf687a31a3adbcb0f7b/Css/news-basic....	1.2 KiB
unicons.iconscout.com/release/v4.0.8/css/line.css	10.9 KiB	930 ms
cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css	27.6 KiB	1.2 s
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.css	5.1 KiB	152 ms
fonts.googleapis.com/css2?family=Manrope:wght@500;700&display=swap	1.1 KiB	760 ms

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
ingestion.webanalytics.italia.it/matomo.js	86400.0 s	65.6 KiB
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js	604800.0 s	43.4 KiB
/maze-universal-loader.js?apiKey=e0283946-5145-4bcc-bfbf-...	43200.0 s	2.9 KiB
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.css	604800.0 s	5.1 KiB

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

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 1.2 s

URL	Time Spent
polimi.it/	1.2 s
www.polimi.it/	0.0 ms

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Diagnostics

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: 640 ms 111.0 KiB

URL	Transfer Size	Est Savings
/typo3temp/assets/bootstrappackage/css/theme-8ec6393bb66a...	49.8 KiB	45.8 KiB
www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Css/polimi.css?1775796139	39.9 KiB	30.6 KiB
cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css	26.8 KiB	24.4 KiB
unicons.iconscout.com/release/v4.0.8/css/line.css	10.2 KiB	10.2 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.

Why this matters

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more ▾

This is the Lighthouse audit fired when too much JS is shipped relative to what executes. The fix isn't a config flag — it requires bundle analysis (webpack-bundle-analyzer, rollup-plugin-visualizer), splitting routes into chunks, lazy-loading off-screen components, and removing unused dependencies. Fundamentally different from minification: minifying reduces byte count, this reduces what's downloaded at all.

Source: Google web.dev / Lighthouse

Estimated savings: 1.8 s 355.9 KiB

URL	Transfer Size	Est Savings
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W&cx=c&gtm=4e64k0	172.9 KiB	116.0 KiB
www.googletagmanager.com/gtm.js?id=GTM-TS7S7BXS	148.9 KiB	80.1 KiB
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W	172.9 KiB	71.0 KiB
ingestion.webanalytics.italia.it/matomo.js	64.3 KiB	38.2 KiB
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js	43.1 KiB	28.0 KiB
ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js	29.8 KiB	22.6 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
Unattributable	2.3 s	33 ms	0.0 ms
www.polimi.it/	1.3 s	133 ms	18 ms
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W	374 ms	297 ms	72 ms
www.googletagmanager.com/gtm.js?id=GTM-TS7S7BXS	265 ms	193 ms	62 ms
/_assets/f34691673face4b5c642d176b42916a9/Library/klaro/k...	240 ms	168 ms	37 ms
/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/...	236 ms	188 ms	3.2 ms
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js	147 ms	23 ms	20 ms
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W&cx=c&gtm=4e64k0	107 ms	34 ms	72 ms
ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js	56 ms	42 ms	12 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
Other	2.6 s
Script Evaluation	1.2 s
Style & Layout	708 ms
Script Parsing & Compilation	324 ms
Rendering	230 ms
Parse HTML & CSS	211 ms

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: 0.0 ms 2.1 KiB

URL	Transfer Size	Est Savings
/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/...	5.3 KiB	2.1 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size
www.polimi.it/fileadmin/asset/video/3_sostenibilita.mp4	9.0 MiB
www.polimi.it/fileadmin/asset/video/2_didattica.mp4	8.9 MiB
www.polimi.it/fileadmin/asset/video/1_ricerca.mp4	8.7 MiB
www.polimi.it/fileadmin/asset/video/0_technology.mp4	4.8 MiB
www.polimi.it/fileadmin/user_upload/news/2026/summer_hp.png	2.7 MiB
www.polimi.it/fileadmin/user_upload/news/2026/Deploy.png	2.7 MiB
www.polimi.it/fileadmin/user_upload/news/rettorato/Rettorato_1920x816_v03.jpg	1.5 MiB
www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Images/borealis.jpg	416.3 KiB
www.polimi.it/fileadmin/asset/video/covers/2_didattica.jpg	380.8 KiB
www.polimi.it/fileadmin/user_upload/news/2026/Firma_Polimi-_Autodromo_Monza.jpg	296.5 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

	URL
div.card__variable-flex > div.card-img-wrapper > picture.focus-adjust > img.w-100 `div.card__variable-flex > div.card-img-wrapper > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/c/3/csm__H0A7518_Rettore_650x533_N...
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-enhance-logo.png
Unitech International `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/Logo_Unitech.png
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-time-logo.png
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/IDEA_League.png

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

●Layout shift culprits

●Optimize DOM size

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●User Timing marks and measures 5 user timings

●Avoid long main-thread tasks 13 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 160 ms

●Server Backend Latencies 360 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 180 ms

○INP breakdown

○Avoid non-composited animations

○Avoid large layout shifts

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.

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
Come funziona l'ammissione `div.card > div.card-img-overlay > div.card-body > h4.card-title`
Entra nella community della prima Università d'Italia `div.contentcontainer > div.contentcontainer-column > div.frame-header > h6.element-header`
Architettura Urbanistica Ingegneria delle Costruzioni `div.col-12 > div.card > div.card-body > h4.card-title`
Raffrescamento sostenibile: lanciata EPIC Deploy `div.card__content > div.card-body > header > h5.card-title`
Convegno Renewable Energy 2026 `div.card__content > div.card-body > header > h6.card-title`
Polimi Community `div.container > div.row > div.col-lg-4 > h4.mb-0`
Sedi `section#footer__accordion > section.footer__headquarters > div#c296 > h6`

These are opportunities to improve keyboard navigation in your application.

Best practices

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. Learn more about touch targets.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
IT `section.footer__header > ul#language_menu_footer > li.active > a`

These items highlight common accessibility best practices.

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` 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

●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.

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

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

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

●`[aria-hidden="true"]` elements do not contain focusable descendents

●Elements use only permitted ARIA attributes

●Background and foreground colors have a sufficient contrast ratio

●Document has a `<title>` element

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

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

●Links 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

●`[lang]` attributes have a valid value

●Skip links are focusable.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●ARIA IDs are unique

●Identical links have the same purpose.

○`[accesskey]` values are unique

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

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

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

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

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

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

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

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

○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.

○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.

○`<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.

○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

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Why this matters

Performance issues directly impact user engagement and conversion rates.

Source	Description
www.polimi.it/	`AbortError: The play() request was interrupted by a call to pause(). https://goo.gl/LdLk22`

●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 issues in the `Issues` panel in Chrome Devtools

●Ensure CSP is effective against XSS attacks

●Use a strong HSTS policy

●Ensure proper origin isolation with COOP

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Mitigate clickjacking with XFO or CSP

SEO

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

Content Best Practices

hreflang links tell search engines what version of a page they should list in search results for a given language or region. Learn more about `hreflang`.

Why this matters

Performance issues directly impact user engagement and conversion rates.


`head > link`
`head > link`
`head > link`

Canonical links suggest which URL to show in search results. Learn more about canonical links.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

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.

1.84 s

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

4.84 s

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

0 ms

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

0.003

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

6.09 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.

4.97 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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Why this matters

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more ▾

Source: Google web.dev / Lighthouse

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.

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.

URL	Est Savings
/_assets/4b51f00386267395f41e0940abbcd656/Css/fonts/icomo...	380 ms

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:2.245 source:map[column:72337 line:13 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js 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:56.05 source:map[type:text value:[unattributed]]] map[reflowTime:2.015 source:map[column:4766 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:7.824 source:map[column:10640 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:1.833 source:map[column:48353 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:0.074 source:map[column:22 line:269 type:source-location url:https://www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/polimi.js?1775796139 urlProvider:network]] map[reflowTime:1.119 source:map[column:180407 line:0 type:source-location url:https://www.polimi.it/_assets/f34691673face4b5c642d176b42916a9/Library/klaro/klaro.js?1765201540 urlProvider:network]]]

Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:label label:Subpart valueType:text] map[key:duration label:Duration valueType:ms]]

items: [map[duration:849.5800002441406 label:Time to first byte subpart:timeToFirstByte] map[duration:618.9709997558593 label:Resource load delay subpart:resourceLoadDelay] map[duration:8731.093 label:Resource load duration subpart:resourceLoadDuration] map[duration:-7444.653 label:Element render delay subpart:elementRenderDelay]]

lhId: page-0-VIDEO

nodeLabel: div#c14813 > div.hero > div.hero__background-image > video#heroVideo-0

path: 1,HTML,1,BODY,4,DIV,4,MAIN,1,DIV,0,DIV,2,DIV,2,VIDEO

selector: div#c14813 > div.hero > div.hero__background-image > video#heroVideo-0

snippet: <video id="heroVideo-0" class="hero-video current" data-index="0" style="position: absolute; top: 0px; left: 0px; width: 100%; height: 100%;" autoplay="" muted="" playsinline="" loop="">

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-VIDEO

nodeLabel: div#c14813 > div.hero > div.hero__background-image > video#heroVideo-0

path: 1,HTML,1,BODY,4,DIV,4,MAIN,1,DIV,0,DIV,2,DIV,2,VIDEO

selector: div#c14813 > div.hero > div.hero__background-image > video#heroVideo-0

snippet: <video id="heroVideo-0" class="hero-video current" data-index="0" style="position: absolute; top: 0px; left: 0px; width: 100%; height: 100%;" autoplay="" muted="" playsinline="" loop="">

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.

title: Preconnected origins

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
/typo3temp/assets/bootstrappackage/css/theme-8ec6393bb66a...	50.1 KiB	171 ms
www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Css/polimi.css?1775796139	40.2 KiB	128 ms
www.polimi.it/_assets/95f1fea155c1725894ea138b1edbb31d/Scss/corsi.css?1775043311	489 B
/_assets/f34691673face4b5c642d176b42916a9/Stylesheet/styl...	5.7 KiB
/typo3temp/assets/css/e7e212200e72edb6153da3c9aedf7517.cs...	582 B
/_assets/f6ef6adaf5c92bf687a31a3adbcb0f7b/Css/news-basic....	1.2 KiB
unicons.iconscout.com/release/v4.0.8/css/line.css	10.8 KiB	234 ms
cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css	27.2 KiB	298 ms
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.css	5.4 KiB
fonts.googleapis.com/css2?family=Manrope:wght@500;700&display=swap	1.1 KiB	208 ms

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
ingestion.webanalytics.italia.it/matomo.js	86400.0 s	65.6 KiB
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js	604800.0 s	43.4 KiB
/maze-universal-loader.js?apiKey=e0283946-5145-4bcc-bfbf-...	43200.0 s	2.9 KiB
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.css	604800.0 s	5.4 KiB

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
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/2026/summer_hp.png	2.7 MiB	2.7 MiB
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/2026/Deploy.png	2.7 MiB	2.7 MiB
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/rettorato/Rettorato_1920x816_v03.jpg	1.5 MiB	1.5 MiB
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/2026/Firma_Polimi-_Autodromo_Monza.jpg	295.8 KiB	273.3 KiB
Build the Future! Scopri il nostro Open Day 2026 Futuri studenti `main#page-content > div.section > div#c18788 > div.banner-cta`	www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Images/borealis.jpg	415.6 KiB	78.1 KiB
Collaborazioni Partnership internazionali Orgogliosamente parte di una rete i… `main#page-content > div.section > div#c771 > div.banner-logos`	/_assets/4b51f00386267395f41e0940abbcd656/Images/banner-l...	149.7 KiB	74.7 KiB
div.frame-group-container > div.frame-group-inner > div.frame-backgroundimage-container > div#frame-backgroundimage-c22291 `div.frame-group-container > div.frame-group-inner > div.frame-backgroundimage-container > div#frame-backgroundimage-c22291`	www.polimi.it/fileadmin/_processed_/d/3/csm_banner-cta-background_13b4354784.png	106.5 KiB	68.4 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/d/3/csm_Card_il_Primo_politecnico_...	79.1 KiB	35.3 KiB
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-enhance-logo.png	32.6 KiB	31.9 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/b/7/csm_047-Hero_Sviluppo_Sostenib...	43.7 KiB	30.6 KiB
Unitech International `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/Logo_Unitech.png	30.3 KiB	28.8 KiB
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-time-logo.png	26.6 KiB	25.6 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/7/d/csm_PolimiSpringGames-200424-9...	38.1 KiB	25.0 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	www.polimi.it/fileadmin/_processed_/f/1/csm_test-04_800x600_06921e914d.jpg	30.8 KiB	17.8 KiB
Ranking internazionali Un’eccellenza in Italia e nel mondo 1° In Italia 98° … `div.container > div.row > div.col-12 > div.card`	/_assets/4b51f00386267395f41e0940abbcd656/Images/card-gfx...	30.3 KiB	16.8 KiB
div.card__variable-flex > div.card-img-wrapper > picture.focus-adjust > img.w-100 `div.card__variable-flex > div.card-img-wrapper > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/c/3/csm__H0A7518_Rettore_650x533_N...	42.1 KiB	14.7 KiB
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/IDEA_League.png	15.1 KiB	14.1 KiB
div.row > div.col-12 > div.card > ::after `div.row > div.col-12 > div.card > ::after`	/_assets/4b51f00386267395f41e0940abbcd656/Images/card-gfx...	27.5 KiB	14.0 KiB

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

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 683 ms

URL	Time Spent
polimi.it/	683 ms
www.polimi.it/	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

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: 50 ms 108.8 KiB

URL	Transfer Size	Est Savings
/typo3temp/assets/bootstrappackage/css/theme-8ec6393bb66a...	49.8 KiB	45.2 KiB
www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Css/polimi.css?1775796139	39.9 KiB	29.6 KiB
cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css	26.8 KiB	24.0 KiB
unicons.iconscout.com/release/v4.0.8/css/line.css	10.0 KiB	10.0 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

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more ▾

Source: Google web.dev / Lighthouse

Estimated savings: 250 ms 356.0 KiB

URL	Transfer Size	Est Savings
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W&cx=c&gtm=4e64k0	172.9 KiB	116.0 KiB
www.googletagmanager.com/gtm.js?id=GTM-TS7S7BXS	148.9 KiB	80.1 KiB
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W	172.9 KiB	71.3 KiB
ingestion.webanalytics.italia.it/matomo.js	64.3 KiB	38.2 KiB
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js	43.1 KiB	27.9 KiB
ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js	29.8 KiB	22.6 KiB

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: 0.0 ms 2.1 KiB

URL	Transfer Size	Est Savings
/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/...	5.3 KiB	2.1 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size
www.polimi.it/fileadmin/asset/video/3_sostenibilita.mp4	8.9 MiB
www.polimi.it/fileadmin/asset/video/2_didattica.mp4	8.9 MiB
www.polimi.it/fileadmin/asset/video/1_ricerca.mp4	8.7 MiB
www.polimi.it/fileadmin/asset/video/0_technology.mp4	8.3 MiB
www.polimi.it/fileadmin/user_upload/news/2026/summer_hp.png	2.7 MiB
www.polimi.it/fileadmin/user_upload/news/2026/Deploy.png	2.7 MiB
www.polimi.it/fileadmin/user_upload/news/rettorato/Rettorato_1920x816_v03.jpg	1.5 MiB
www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Images/borealis.jpg	416.3 KiB
www.polimi.it/fileadmin/asset/video/covers/2_didattica.jpg	380.8 KiB
www.polimi.it/fileadmin/user_upload/news/2026/Firma_Polimi-_Autodromo_Monza.jpg	296.5 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

	URL
div.card__variable-flex > div.card-img-wrapper > picture.focus-adjust > img.w-100 `div.card__variable-flex > div.card-img-wrapper > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/c/3/csm__H0A7518_Rettore_650x533_N...
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-enhance-logo.png
Unitech International `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/Logo_Unitech.png
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-time-logo.png
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/IDEA_League.png

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

●Layout shift culprits

●Optimize DOM size

●Modern HTTP

●Optimize viewport for mobile

●Max Potential First Input Delay 40 ms

●Minify CSS

●User Timing marks and measures 5 user timings

●JavaScript execution time 0.3 s

●Minimizes main-thread work 1.4 s

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 160 ms

●Server Backend Latencies 370 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 180 ms

●Avoid large layout shifts 1 layout shift found

○INP breakdown

○Avoid long main-thread tasks

○Avoid non-composited animations

Accessibility

Navigation

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Come funziona l'ammissione `div.card > div.card-img-overlay > div.card-body > h4.card-title`
Entra nella community della prima Università d'Italia `div.contentcontainer > div.contentcontainer-column > div.frame-header > h6.element-header`
Architettura Urbanistica Ingegneria delle Costruzioni `div.col-12 > div.card > div.card-body > h4.card-title`
Raffrescamento sostenibile: lanciata EPIC Deploy `div.card__content > div.card-body > header > h5.card-title`
Convegno Renewable Energy 2026 `div.card__content > div.card-body > header > h6.card-title`
Polimi Community `div.container > div.row > div.col-lg-4 > h4.mb-0`
Sedi `section#footer__accordion > section.footer__headquarters > div#c296 > h6`

These are opportunities to improve keyboard navigation in your application.

Tables and lists

Screen readers have a specific way of announcing lists. Ensuring proper list structure aids screen reader output. Learn more about proper list structure.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Il Politecnico Formazione Dottorato Ricerca Sviluppo sostenibile Campus e servi… `div.row > div.col-7 > nav.navbar > ul.navbar-nav`

These are opportunities to improve the experience of reading tabular or list data using assistive technology, like a screen reader.

Best practices

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. Learn more about touch targets.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
IT `section.footer__header > ul#language_menu_footer > li.active > a`

These items highlight common accessibility best practices.

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` 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

●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.

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

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

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

●`[aria-hidden="true"]` elements do not contain focusable descendents

●Elements use only permitted ARIA attributes

●Background and foreground colors have a sufficient contrast ratio

●Document has a `<title>` element

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

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

●Links are distinguishable without relying on color.

●Links have a discernible name

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

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

●`[lang]` attributes have a valid value

●Skip links are focusable.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●ARIA IDs are unique

●`<video>` elements contain a `<track>` element with `[kind="captions"]`

●Identical links have the same purpose.

○`[accesskey]` values are unique

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

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

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

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

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

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

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

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

○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.

○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.

○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.

○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.

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 DOM-based XSS with Trusted Types

●Detected JavaScript libraries

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Mitigate clickjacking with XFO or CSP

SEO

Content Best Practices

hreflang links tell search engines what version of a page they should list in search results for a given language or region. Learn more about `hreflang`.

Why this matters

Performance issues directly impact user engagement and conversion rates.


`head > link`
`head > link`
`head > link`

Canonical links suggest which URL to show in search results. Learn more about canonical links.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

Results for https://polimi.it

Site Health

How you compare

Top Priorities (5)

Fix Priority Matrix

Quick Wins

Strategic

Easy Improvements

Deprioritize

What fixing these means

Conversion Barriers

Speed (2)

Trust (2)

Navigation (2)

Return on Investment

Investment

Monthly returns

Regulatory risk avoided

Payback period

Estimated Remediation Cost

Cost by category

Cost by effort level

What Inaction Is Costing You

Compliance Risk

Bandwidth Waste

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Navigation

Best practices

Best Practices

General

SEO

Content Best Practices

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Navigation

Tables and lists

Best practices

Best Practices

SEO

Content Best Practices

Keyboard Shortcuts