Performance
· 15 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.
1.60 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
2.14 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
14 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.
1.80 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.
2.14 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 BudgetAction5.1 MB transferred, 80 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
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DPage Weight InventoryAction80 resources · 5.1 MB · 115 KB savings availableFIX
~114.6 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 80 resources | 5.1 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction53 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
BJS Execution Cost724ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.labiennale.org/it | 287ms | 1ms | 1ms | 3rd |
| https://static.labiennale.org/files/js/js_siAzsLQXar6_8hnne92BaBQNphQqqLqTxKnhobUkxPk.js | 203ms | 98ms | 4ms | 3rd |
| Unattributable | 105ms | 2ms | 0ms | 3rd |
| https://consent.cookiebot.com/74679177-89ae-4133-b283-6728c4a7e16f/cc.js?renew=false&referer=www.labiennale.org&dnt=false&init=false | 72ms | 30ms | 11ms | 3rd |
| https://static.labiennale.org/files/js/js_T_s-Vel_gIhI-8pVHSpMba7BFDRWM7Vrs9weHs-QaJ4.js | 57ms | 22ms | 20ms | 3rd |
CJS BundlesAction9 scripts, 115 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://static.labiennale.org/files/js/js_T_s-Vel_gIhI-8pVHSpMba7BFDRWM7Vrs9weHs-QaJ4.js | 143 KB | 90 KB (63%) | ✗ | 3rd |
| https://consent.cookiebot.com/74679177-89ae-4133-b283-6728c4a7e16f/cc.js?renew=false&referer=www.labiennale.org&dnt=false&init=false | 101 KB | 25 KB (25%) | ✓ | 3rd |
| https://consent.cookiebot.com/uc.js | 27 KB | — | ✓ | 3rd |
| https://static.labiennale.org/files/js/js_siAzsLQXar6_8hnne92BaBQNphQqqLqTxKnhobUkxPk.js | 39 KB | — | ✗ | 3rd |
| https://static.labiennale.org/files/js/js_gTd4U5Ixr7jD6Iy1a-AnwhsWJMyfk9VI4tcTJaYAt8E.js | 13 KB | — | ✗ | 3rd |
| https://static.labiennale.org/files/js/js_t14MH5HMpIPvofj11pf8xgDNdp6s_8vYGQ7h2fsHpiY.js | 11 KB | — | ✗ | 3rd |
| https://static.labiennale.org/files/js/js_oYVKp-cluFZQnjxYMtXDmhZY3bwT8PYHYk6oiRMAQDw.js | 2 KB | — | ✓ | 3rd |
| https://static.labiennale.org/files/js/js_koKqZylAHdvmXNtCfSAUlrok3mcbuKixJGQlDEbHwoI.js | 1 KB | — | ✓ | 3rd |
| https://static.labiennale.org/files/js/js_L50O_PWoAuMOxVjnzZCkNSSmI0kFwhZsO1_KS8WnGKw.js | 2 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
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 Loading8 fonts (112 KB)PASS
Web fonts
8
112 KB total
Render-blocking
0
of 8
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
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 ~2 KB and ~4 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
Network Waterfall80 requests over 1794msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.labiennale.org www.labiennale.org | Other | 287ms | 15 KB | — | €3/mo | Costly |
static.labiennale.org static.labiennale.org | Other | 203ms | 39 KB | — | €2/mo | Costly |
Unattributable Unattributable | Other | 105ms | 0 KB | — | €1/mo | Optional |
consent.cookiebot.com consent.cookiebot.com | Other | 72ms | 101 KB | 25% | €1/mo | Optional |
static.labiennale.org static.labiennale.org | Other | 57ms | 143 KB | 63% | €1/mo | Optional |
These scripts may cost more than they're worth
- www.labiennale.org adds 287ms and costs ~€3/month
- static.labiennale.org adds 203ms 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.labiennale.org takes 287ms 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
static.labiennale.org takes 203ms 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
63% of static.labiennale.org'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