Performance
· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
2.77 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
5.83 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
214 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.
3.37 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.
6.93 s
Page Load Progression
375 ms
750 ms
1.1 s
1.5 s
1.9 s 2.2 s 2.6 s 3.0 sFPage Weight BudgetAction3.2 MB transferred, 122 requestsFIX
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.
Source: web.dev
Subset fonts to include only used characters, or switch to system font stacks.
Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).
Source: web.dev font loading
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.
Source: web.dev
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DPage Weight InventoryAction122 resources · 3.2 MB · 148 KB savings availableFIX
~148.2 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 122 resources | 3.2 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction35 images, 0 KB saveableREVIEW
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
CJS Execution CostAction1557ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.unimi.it/it | 596ms | 22ms | 1ms | 3rd |
| Unattributable | 596ms | 18ms | 0ms | 3rd |
| https://cdn.jsdelivr.net/gh/jfeltkamp/cookiesjsr@1/dist/cookiesjsr.min.js?v=1.0.13 | 234ms | 191ms | 41ms | 3rd |
| https://www.unimi.it/sites/default/files/js/js_D5bFiBxgILkRdIbIOnwo3oMVWRVQ7qgMa1vFjcHMGP4.js?scope=footer&delta=0&language=it&theme=unimi&include=eJxtj2EOwjAIhS_UjCM1bMXKbEtDqTpPrybb1MU_8N7HC4FRxJopVhg35auS58LmdgRVqlxJv4iJJOPqJpELU4O1z02HKZQN-xMnI4Vfu08jAhZMi_HUPtAwwru8iBIE7RXTEBiTxAFnvLsoEhP5PXfwf0LZ9de1mUqHTbheODNgVZ7O3AOvYH9x9TXhQuqVGj9oZYcdN2Sf0STLE-Avg7w | 131ms | 85ms | 39ms | 3rd |
BJS Bundles9 scripts, 148 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.unimi.it/sites/default/files/js/js_D5bFiBxgILkRdIbIOnwo3oMVWRVQ7qgMa1vFjcHMGP4.js?scope=footer&delta=0&language=it&theme=unimi&include=eJxtj2EOwjAIhS_UjCM1bMXKbEtDqTpPrybb1MU_8N7HC4FRxJopVhg35auS58LmdgRVqlxJv4iJJOPqJpELU4O1z02HKZQN-xMnI4Vfu08jAhZMi_HUPtAwwru8iBIE7RXTEBiTxAFnvLsoEhP5PXfwf0LZ9de1mUqHTbheODNgVZ7O3AOvYH9x9TXhQuqVGj9oZYcdN2Sf0STLE-Avg7w | 87 KB | 64 KB (73%) | ✓ | 3rd |
| https://cdn.jsdelivr.net/gh/jfeltkamp/cookiesjsr@1/dist/cookiesjsr.min.js?v=1.0.13 | 102 KB | 46 KB (46%) | ✓ | 3rd |
| https://ingestion.webanalytics.italia.it/matomo.js | 66 KB | 38 KB (59%) | ✓ | 3rd |
| https://www.unimi.it/sites/default/files/js/js_SzvMUckLlBi1wNgXTMliAaqNqUS1M_61g-xZ-AEus-o.js?scope=header&delta=0&language=it&theme=unimi&include=eJxtj2EOwjAIhS_UjCM1bMXKbEtDqTpPrybb1MU_8N7HC4FRxJopVhg35auS58LmdgRVqlxJv4iJJOPqJpELU4O1z02HKZQN-xMnI4Vfu08jAhZMi_HUPtAwwru8iBIE7RXTEBiTxAFnvLsoEhP5PXfwf0LZ9de1mUqHTbheODNgVZ7O3AOvYH9x9TXhQuqVGj9oZYcdN2Sf0STLE-Avg7w | 8 KB | — | ✓ | 3rd |
| https://www.unimi.it/sites/default/files/js/js_QnmgZaJ9at2Cy2RKy0fTl-3cju0hQ61fetYV77gkeoM.js?scope=footer&delta=2&language=it&theme=unimi&include=eJxtj2EOwjAIhS_UjCM1bMXKbEtDqTpPrybb1MU_8N7HC4FRxJopVhg35auS58LmdgRVqlxJv4iJJOPqJpELU4O1z02HKZQN-xMnI4Vfu08jAhZMi_HUPtAwwru8iBIE7RXTEBiTxAFnvLsoEhP5PXfwf0LZ9de1mUqHTbheODNgVZ7O3AOvYH9x9TXhQuqVGj9oZYcdN2Sf0STLE-Avg7w | 21 KB | — | ✓ | 3rd |
| https://www.unimi.it/sites/default/files/js/js_7k7SnMTv-CEzN_7XJJ6jmROJmFBcHVsnNmWC5BzSt_M.js?scope=footer&delta=4&language=it&theme=unimi&include=eJxtj2EOwjAIhS_UjCM1bMXKbEtDqTpPrybb1MU_8N7HC4FRxJopVhg35auS58LmdgRVqlxJv4iJJOPqJpELU4O1z02HKZQN-xMnI4Vfu08jAhZMi_HUPtAwwru8iBIE7RXTEBiTxAFnvLsoEhP5PXfwf0LZ9de1mUqHTbheODNgVZ7O3AOvYH9x9TXhQuqVGj9oZYcdN2Sf0STLE-Avg7w | 13 KB | — | ✓ | 3rd |
| https://www.unimi.it/modules/contrib/cookies/js/cookiesjsr.conf.js?v=10.5.1 | 1 KB | — | ✓ | 3rd |
| https://cdn.jsdelivr.net/gh/jfeltkamp/cookiesjsr@1/dist/cookiesjsr-preloader.min.js | 8 KB | — | ✓ | 3rd |
| https://static.cloudflareinsights.com/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da1771523124516 | 11 KB | — | ✓ | 3rd |
Consider code splitting or tree shaking to reduce unused code.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
Consider code splitting or tree shaking to reduce unused code.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
Consider code splitting or tree shaking to reduce unused code.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+Font Loading7 fonts (340 KB)PASS
Web fonts
7
340 KB total
Render-blocking
0
of 7
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
Optimization checklist
- Preload critical fonts (priority=high)
- Use woff2 format for all fonts
- Set font-display to swap, optional, or fallback
- Subset large fonts (≤100 KB each)
Fixing the unchecked items could save ~77 KB and ~154 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall122 requests over 1903msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.unimi.it www.unimi.it | Other | 596ms | 19 KB | — | €3/mo | Costly |
Unattributable Unattributable | Other | 596ms | 0 KB | — | €3/mo | Costly |
jsDelivr cdn.jsdelivr.net | CDN | 234ms | 102 KB | 46% | €1/mo | Costly |
www.unimi.it www.unimi.it | Other | 131ms | 87 KB | 73% | €1/mo | Optional |
These scripts may cost more than they're worth
- www.unimi.it adds 596ms and costs ~€3/month
- Unattributable adds 596ms and costs ~€3/month
- jsDelivr adds 234ms and costs ~€1/month
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.
Learn more ▾ ▴
Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.
Source: web.dev
www.unimi.it takes 596ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
Unattributable takes 596ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
jsDelivr takes 234ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
73% of www.unimi.it's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev