Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
C
Image Optimization
Action
117 images, 0 KB saveable
REVIEW
117 images, 0 KB saveable
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2021/1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2016/0... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/1440x-/dl/img/2026... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2016/0... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2016/0... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2021/1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2021/1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2016/0... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2020/0... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2021/1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2016/0... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2021/1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2021/1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2021/1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.raiplay.it/resizegd/-x28/dl/img/2021/1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
117images1.6 MB
0oversized-0 KB
14legacy format
15missing dimensionsCLS risk
Set explicit width and height to prevent CLS.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
B
HTTP/3 (QUIC)
HTTP/3 not advertised
REVIEW
HTTP/3 not advertised
Info::
i
HTTP/3 (QUIC) is not advertised
HTTP/3 isn't advertised via Alt-Svc and the worker didn't negotiate h3. HTTP/3 reduces handshake latency (1-RTT instead of 2-3 RTTs) and is more resilient on lossy connections. Most modern CDNs (Cloudflare, Fastly, AWS CloudFront, Google Cloud CDN) support HTTP/3 with a single config switch -- consider enabling for mobile-heavy workloads.
C
Compression Algorithm
Action
Main response served uncompressed
REVIEW
Main response served uncompressed
Info::
i
Main HTML response has no Content-Encoding (uncompressed)
The main HTML document is served without compression. The Text Compression section above lists the broader picture; for the main response specifically, even gzip would shave ~70-80% off most text payloads.
B
Main HTML Cache-Control
No Cache-Control header on main HTML response
REVIEW
No Cache-Control header on main HTML response
Info::
i
Main HTML response has no Cache-Control header
Without an explicit Cache-Control, browsers fall back to heuristic caching (~10% of Last-Modified age). Set `Cache-Control: no-cache` or `max-age=300` for HTML to control freshness explicitly -- prevents stale auth state and SPA shell drift.
B
Server-Timing Observability
No Server-Timing header found
REVIEW
No Server-Timing header found
Info::
i
No Server-Timing header found
Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW
Green Hosting
No green hosting detected
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
✓
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
7 fonts (159 KB)
PASS
7 fonts (159 KB)
Info::
i
7 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
7
159 KB total
Render-blocking
0
of 7
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
Montserrat-Regular.woff2woff2swap
Size19 KB
Load time61 ms
Start676 ms
RiskFOUT — text flashes from fallback to web font
Montserrat-SemiBold.woff2woff2swap
Size19 KB
Load time72 ms
Start677 ms
RiskFOUT — text flashes from fallback to web font
Montserrat-Bold.woff2woff2swap
Size19 KB
Load time63 ms
Start677 ms
RiskFOUT — text flashes from fallback to web font
font-woff;charset=utf-8...woffswap
Size2 KB
Load time747 ms
Start2.4 s
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
UcC73FwrK3iLTeHuS_fvQtM...woff2swap
Size45 KB
Load time69 ms
Start2.4 s
RiskFOUT — text flashes from fallback to web font
Inter.woff2woff2swap
Size46 KB
Load time241 ms
Start2.8 s
RiskFOUT — text flashes from fallback to web font
font-woff;charset=utf-8...woffswap
Size10 KB
Load time163 ms
Start3.2 s
RiskFOUT — text flashes from fallback to web font
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 ~3 KB and ~6 ms
A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
✓
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
✓
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
✓
No resource hint issues
A+
LCP Image Preload
LCP preload audit not available
PASS
LCP preload audit not available
Info::
✓
LCP image preload audit not available for this scan
A+
Server Response Intelligence
1 server-response signal(s) detected
PASS
1 server-response signal(s) detected
Info::
i
No `ETag` or `Last-Modified` -- conditional GET not supported
Without either header, browsers can't issue conditional GETs and refresh always re-downloads the full response body even when nothing changed. Add `ETag: "<hash>"` (or `Last-Modified: <date>`) on cacheable responses; the server returns 304 Not Modified when the client's cached copy is still valid, saving bandwidth.
Network Waterfall
221 requests over 7858ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
88%of JavaScript execution is third-party
First-party Third-party4070ms · 1745KB · €44/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
www.raiplay.it
www.raiplay.it
Other
1178ms
214 KB
—
€13/mo
Costly
www.raiplay.it
www.raiplay.it
Other
1119ms
37 KB
—
€12/mo
Costly
www.raiplay.it
www.raiplay.it
Other
370ms
57 KB
43%
€4/mo
Costly
www.raiplay.it
www.raiplay.it
Other
327ms
124 KB
49%
€4/mo
Costly
www.raiplay.it
www.raiplay.it
Other
254ms
665 KB
84%
€3/mo
Costly
www.raiplay.it
www.raiplay.it
Other
235ms
82 KB
56%
€3/mo
Costly
cdns.gigya.com
cdns.gigya.com
Other
138ms
209 KB
56%
€2/mo
Optional
www.raiplay.it
www.raiplay.it
Other
137ms
25 KB
—
€1/mo
Optional
www.raiplay.it
www.raiplay.it
Other
98ms
22 KB
—
€1/mo
Optional
www.raiplay.it
www.raiplay.it
Other
88ms
30 KB
73%
€1/mo
Optional
www.raiplay.it
www.raiplay.it
Other
63ms
270 KB
69%
€1/mo
Optional
www.raiplay.it
www.raiplay.it
Other
61ms
10 KB
—
€1/mo
Optional
www.raiplay.it
Other
Costly
Execution1178ms
Transfer214 KB
Monthly Cost€13/mo
www.raiplay.it
Other
Costly
Execution1119ms
Transfer37 KB
Monthly Cost€12/mo
www.raiplay.it
Other
Costly
Execution370ms
Transfer57 KB
Unused43%
Monthly Cost€4/mo
www.raiplay.it
Other
Costly
Execution327ms
Transfer124 KB
Unused49%
Monthly Cost€4/mo
www.raiplay.it
Other
Costly
Execution254ms
Transfer665 KB
Unused84%
Monthly Cost€3/mo
www.raiplay.it
Other
Costly
Execution235ms
Transfer82 KB
Unused56%
Monthly Cost€3/mo
cdns.gigya.com
Other
Optional
Execution138ms
Transfer209 KB
Unused56%
Monthly Cost€2/mo
www.raiplay.it
Other
Optional
Execution137ms
Transfer25 KB
Monthly Cost€1/mo
www.raiplay.it
Other
Optional
Execution98ms
Transfer22 KB
Monthly Cost€1/mo
www.raiplay.it
Other
Optional
Execution88ms
Transfer30 KB
Unused73%
Monthly Cost€1/mo
www.raiplay.it
Other
Optional
Execution63ms
Transfer270 KB
Unused69%
Monthly Cost€1/mo
www.raiplay.it
Other
Optional
Execution61ms
Transfer10 KB
Monthly Cost€1/mo
These scripts may cost more than they're worth
www.raiplay.it adds 1178ms and costs ~€13/month
www.raiplay.it adds 1119ms and costs ~€12/month
www.raiplay.it adds 370ms and costs ~€4/month
www.raiplay.it adds 327ms and costs ~€4/month
www.raiplay.it adds 254ms and costs ~€3/month
www.raiplay.it adds 235ms and costs ~€3/month
88% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
Why this matters
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.raiplay.it takes 1178ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.raiplay.it takes 1119ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.raiplay.it takes 370ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.raiplay.it takes 327ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.raiplay.it takes 254ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
84% of www.raiplay.it's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
www.raiplay.it takes 235ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
56% of www.raiplay.it's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
56% of cdns.gigya.com's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
73% of www.raiplay.it's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
69% of www.raiplay.it's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.