Performance
· 26 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.
2.64 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
5.37 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
1.72 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.042
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
5.01 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.
14.74 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction8574ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://cdn.prod.website-files.com/60c61592c3ee5b9a0b6c342a/js/webflow.schunk.2df18e42ad7c0320.js | 2273ms | 374ms | 80ms | 3rd |
| https://www.serenis.it/ | 1445ms | 126ms | 14ms | 3rd |
| Unattributable | 952ms | 19ms | 0ms | 1st |
| https://www.redditstatic.com/ads/pixel.js | 678ms | 639ms | 8ms | 3rd |
| https://gtm.serenis.it/gtm.js?id=GTM-TFFTF9G | 614ms | 523ms | 78ms | 3rd |
| https://cdn.jsdelivr.net/npm/lumious-components@1.0.6/component/ticker.js | 520ms | 429ms | 0ms | 3rd |
| https://gtm.serenis.it/gtag/js?id=G-NJE24PT4YX&cx=c>m=4e68j0&sign=7822a9ad737c8b5888a26f3c708d7d25576ba4df981b9b950838b49cbce7e9a9_20260821 | 494ms | 429ms | 62ms | 3rd |
| https://cdn.prod.website-files.com/60c61592c3ee5b9a0b6c342a/js/webflow.fc25d11b.df955deb112b756b.js | 470ms | 461ms | 1ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-330328704&cx=c>m=4e68j0&sign=7822a9ad737c8b5888a26f3c708d7d25576ba4df981b9b950838b49cbce7e9a9_20260821 | 326ms | 271ms | 54ms | 3rd |
| https://cdn.iubenda.com/cookie_solution/iubenda_cs/1.104.3/core-it.js | 316ms | 261ms | 42ms | 3rd |
Showing top 10 of 14 scripts
DPage Weight InventoryAction86 resources · 1.6 MB · 284 KB savings availableFIX
~283.6 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 86 resources | 1.6 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CPage Weight BudgetAction1.6 MB transferred, 86 requestsREVIEW
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
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
CImage OptimizationAction32 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
CJS BundlesAction26 scripts, 284 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://gtm.serenis.it/gtag/js?id=G-NJE24PT4YX&cx=c>m=4e68j0&sign=7822a9ad737c8b5888a26f3c708d7d25576ba4df981b9b950838b49cbce7e9a9_20260821 | 209 KB | 81 KB (39%) | ✓ | 3rd |
| https://gtm.serenis.it/gtm.js?id=GTM-TFFTF9G | 217 KB | 71 KB (33%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-330328704&cx=c>m=4e68j0&sign=7822a9ad737c8b5888a26f3c708d7d25576ba4df981b9b950838b49cbce7e9a9_20260821 | 154 KB | 67 KB (44%) | ✓ | 3rd |
| https://cdn.iubenda.com/cookie_solution/iubenda_cs/1.104.3/core-it.js | 113 KB | 65 KB (58%) | ✓ | 3rd |
| https://cdn.iubenda.com/cs/gpp/stub.js | 3 KB | — | ✓ | 3rd |
| https://cdn.prod.website-files.com/60c61592c3ee5b9a0b6c342a/js/webflow.schunk.36b8fb49256177c8.js | 14 KB | — | ✓ | 3rd |
| https://player.vimeo.com/api/player.js | 9 KB | — | ✓ | 3rd |
| https://keus-vimeo.s3.eu-south-1.amazonaws.com/keus-vimeo.js | 3 KB | — | ✓ | 3rd |
| https://cdnjs.cloudflare.com/ajax/libs/OwlCarousel2/2.3.4/owl.carousel.min.js | 11 KB | — | ✓ | 3rd |
| https://cdn.jsdelivr.net/npm/lumious-components@1.0.6/component/ticker.js | 1 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
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
BHTTP/3 (QUIC)HTTP/3 not advertisedREVIEW
CCompression AlgorithmActionMain response served uncompressedREVIEW
BMain HTML Cache-ControlNo Cache-Control header on main HTML responseREVIEW
BServer-Timing ObservabilityNo Server-Timing header foundREVIEW
BJavaScript Blocking2 JS blocking issue(s) detectedREVIEW
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 Loading4 fonts (217 KB)PASS
Web fonts
4
217 KB total
Render-blocking
0
of 4
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 ~65 KB and ~130 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
AResource Hints6 hints, 0 missing preconnectsPASS
Current Resource Hints
6 resource hints configured
preconnect already does the DNS lookup; adding dns-prefetch to the same origin is at best a no-op. Sample: https://cdn.iubenda.com. Remove the redundant dns-prefetch entries.
Performance issues directly impact user engagement and conversion rates.
The same href shouldn't appear in multiple hint rels -- one wins, the others are wasted markup and may confuse cache behavior. Sample: https://cdn.iubenda.com (preconnect+dns-prefetch).
Performance issues directly impact user engagement and conversion rates.
A+LCP Image PreloadLCP preload audit not availablePASS
A+Server Response Intelligence1 server-response signal(s) detectedPASS
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
A+CSS Performance DepthNo CSS performance depth issues detectedPASS
Network Waterfall86 requests over 6197msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
cdn.prod.website-files.com cdn.prod.website-files.com | Other | 2273ms | 76 KB | — | €33/mo | Costly |
www.serenis.it www.serenis.it | Other | 1445ms | 34 KB | — | €21/mo | Costly |
www.redditstatic.com www.redditstatic.com | Other | 678ms | 20 KB | — | €10/mo | Costly |
gtm.serenis.it gtm.serenis.it | Other | 614ms | 217 KB | 33% | €9/mo | Costly |
jsDelivr cdn.jsdelivr.net | CDN | 520ms | 1 KB | — | €8/mo | Costly |
gtm.serenis.it gtm.serenis.it | Other | 494ms | 209 KB | 39% | €7/mo | Costly |
cdn.prod.website-files.com cdn.prod.website-files.com | Other | 470ms | 1 KB | — | €7/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 326ms | 154 KB | 44% | €5/mo | Costly |
Iubenda cdn.iubenda.com | Consent | 316ms | 113 KB | 58% | €5/mo | Essential |
d3e54v103j8qbb.cloudfront.net d3e54v103j8qbb.cloudfront.net | Other | 273ms | 30 KB | — | €4/mo | Costly |
widget.trustpilot.com widget.trustpilot.com | Other | 100ms | 8 KB | — | €1/mo | Optional |
assets.customer.io assets.customer.io | Other | 61ms | 3 KB | — | €1/mo | Optional |
cdn.prod.website-files.com cdn.prod.website-files.com | Other | 51ms | 91 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- cdn.prod.website-files.com adds 2273ms and costs ~€33/month
- www.serenis.it adds 1445ms and costs ~€21/month
- www.redditstatic.com adds 678ms and costs ~€10/month
- gtm.serenis.it adds 614ms and costs ~€9/month
- jsDelivr adds 520ms and costs ~€8/month
- gtm.serenis.it adds 494ms and costs ~€7/month
- cdn.prod.website-files.com adds 470ms and costs ~€7/month
- Google Tag Manager adds 326ms and costs ~€5/month
- d3e54v103j8qbb.cloudfront.net adds 273ms and costs ~€4/month
89% 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
cdn.prod.website-files.com takes 2273ms 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.serenis.it takes 1445ms 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.redditstatic.com takes 678ms 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
gtm.serenis.it takes 614ms 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 520ms 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
gtm.serenis.it takes 494ms 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.prod.website-files.com takes 470ms 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 326ms 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
58% of Iubenda'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
d3e54v103j8qbb.cloudfront.net takes 273ms 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
Image Optimization156 images, 0 KB total, 0 KB wastedINFO
Image Optimization Audit
Total Images
156
Total Size
0 KB
Oversized
1