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.
3.84 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
12.36 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
2.76 s
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.
11.26 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.
26.81 s
Page Load Progression
2.2 s
4.5 s
6.7 s
8.9 s
11.2 s
13.4 s
15.6 s
17.9 sFPage Weight BudgetAction18.5 MB transferred, 195 requestsFIX
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.
Source: web.dev
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
FJS Execution CostAction24785ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.unipd.it/_next/static/chunks/3bc8e9950183d5ef.js | 9716ms | 1788ms | 2ms | 3rd |
| https://www.unipd.it/ | 7287ms | 51ms | 248ms | 3rd |
| https://www.unipd.it/_next/static/chunks/da8a57391d249a2f.js | 3632ms | 2523ms | 22ms | 3rd |
| Unattributable | 1980ms | 37ms | 0ms | 3rd |
| https://consent.cookiebot.eu/uc.js?cbid=6ac4eb1a-01b6-4600-be5d-a4ef2ebdd213&implementation=gtm&consentmode-dataredaction=dynamic | 486ms | 301ms | 9ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-608956197&cx=c>m=4e64k1h2 | 375ms | 308ms | 61ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-NC7RRGD | 288ms | 235ms | 41ms | 3rd |
| https://cdn.eye-able.com/public/js/eyeAble.js | 231ms | 149ms | 56ms | 3rd |
| https://www.unipd.it/_next/static/chunks/ee00070b57b20554.js | 230ms | 47ms | 13ms | 3rd |
| https://www.googletagmanager.com/gtag/destination?id=AW-11111625403&cx=c>m=4e64k1h2 | 213ms | 172ms | 38ms | 3rd |
Showing top 10 of 14 scripts
FJS BundlesAction53 scripts, 567 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://cdn.eye-able.com/public/js/eyeAble.js | 145 KB | 101 KB (70%) | ✓ | 3rd |
| https://www.unipd.it/_next/static/chunks/99b45d2424516508.js | 123 KB | 94 KB (77%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-B3WV5DRLH0&cx=c>m=4e64k1h2 | 135 KB | 83 KB (61%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/destination?id=AW-11111625403&cx=c>m=4e64k1h2 | 143 KB | 67 KB (47%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-NC7RRGD | 151 KB | 61 KB (40%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-608956197&cx=c>m=4e64k1h2 | 174 KB | 60 KB (35%) | ✓ | 3rd |
| https://ingestion.webanalytics.italia.it/matomo.js | 66 KB | 36 KB (57%) | ✓ | 3rd |
| https://www.unipd.it/_next/static/chunks/ee00070b57b20554.js | 40 KB | 22 KB (55%) | ✓ | 3rd |
| https://www.unipd.it/_next/static/chunks/c49deea11a2ca976.js | 22 KB | 21 KB (99%) | ✓ | 3rd |
| https://www.unipd.it/_next/static/chunks/da8a57391d249a2f.js | 66 KB | 21 KB (32%) | ✓ | 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
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
FPage Weight InventoryAction195 resources · 18.5 MB · 567 KB savings availableFIX
~566.7 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 195 resources | 18.5 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization43 images, 0 KB saveableREVIEW
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 Loading5 fonts (962 KB)PASS
Web fonts
5
962 KB total
Render-blocking
0
of 5
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Convert to woff2 for ~30% smaller file size
- 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 ~657 KB and ~1314 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 Waterfall195 requests over 43343msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.unipd.it www.unipd.it | Other | 9716ms | 7 KB | — | €105/mo | Costly |
www.unipd.it www.unipd.it | Other | 7287ms | 333 KB | — | €79/mo | Costly |
www.unipd.it www.unipd.it | Other | 3632ms | 66 KB | 32% | €39/mo | Costly |
Unattributable Unattributable | Other | 1980ms | 0 KB | — | €21/mo | Costly |
consent.cookiebot.eu consent.cookiebot.eu | Other | 486ms | 30 KB | — | €5/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 375ms | 174 KB | 35% | €4/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 288ms | 151 KB | 40% | €3/mo | Costly |
cdn.eye-able.com cdn.eye-able.com | Other | 231ms | 145 KB | 70% | €3/mo | Costly |
www.unipd.it www.unipd.it | Other | 230ms | 40 KB | 55% | €2/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 213ms | 143 KB | 47% | €2/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 152ms | 135 KB | 61% | €2/mo | Optional |
www.unipd.it www.unipd.it | Other | 76ms | 25 KB | — | €1/mo | Optional |
www.unipd.it www.unipd.it | Other | 70ms | 23 KB | — | €1/mo | Optional |
www.unipd.it www.unipd.it | Other | 50ms | 123 KB | 77% | €1/mo | Optional |
These scripts may cost more than they're worth
- www.unipd.it adds 9716ms and costs ~€105/month
- www.unipd.it adds 7287ms and costs ~€79/month
- www.unipd.it adds 3632ms and costs ~€39/month
- Unattributable adds 1980ms and costs ~€21/month
- consent.cookiebot.eu adds 486ms and costs ~€5/month
- Google Tag Manager adds 375ms and costs ~€4/month
- Google Tag Manager adds 288ms and costs ~€3/month
- cdn.eye-able.com adds 231ms and costs ~€3/month
- www.unipd.it adds 230ms and costs ~€2/month
- Google Tag Manager adds 213ms and costs ~€2/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.unipd.it takes 9716ms 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
www.unipd.it takes 7287ms 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
www.unipd.it takes 3632ms 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 1980ms 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
consent.cookiebot.eu takes 486ms 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
Google Tag Manager takes 375ms 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
Google Tag Manager takes 288ms 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
cdn.eye-able.com takes 231ms 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
70% of cdn.eye-able.com'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
www.unipd.it takes 230ms 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
55% of www.unipd.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
Google Tag Manager takes 213ms 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
61% of Google Tag Manager'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
77% of www.unipd.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