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
Page Weight Budget
Action
2.0 MB transferred, 73 requests
REVIEW
2.0 MB transferred, 73 requests
Info::
i
Page weighs 3.7 MB (2.0 MB transferred)
Warning::
!
JavaScript is 937 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 937 KB
Info::
i
73 HTTP requests
Info::
i
Estimated 0.42 g CO2 per page load
2.0 MBtransferred
73 requests
0.42 g CO2 per page load
JavaScript937.0 KiB45%
Images884.2 KiB43%
Fonts146.2 KiB7%
CSS82.3 KiB4%
HTML13.0 KiB1%
Other1018 B0%
Other594 B0%
Other572 B0%
Other561 B0%
Other0 B0%
02.4 MB4.9 MB
Approaching limit
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Why this matters
JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.
Source: web.dev
B
Image Optimization
14 images, 0 KB saveable
REVIEW
14 images, 0 KB saveable
Info::
✓
All images are well-optimized
14images884 KB
0oversized-0 KB
14legacy format
0missing dimensionsCLS risk
C
Document Compression
Action
Document response served uncompressed
REVIEW
Document 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.
C
Asset Compression
Action
1 of 4 asset hosts serve text uncompressed
REVIEW
1 of 4 asset hosts serve text uncompressed
Info::
i
www.fabioantichi.it serves assets with gzip; brotli would be ~20% smaller (assets: 70)
Every current browser accepts brotli. On a CDN this is a per-pull-zone toggle (Cloudflare, Fastly, CloudFront, CDN77, Bunny all expose it); on an origin it needs the brotli module (nginx-brotli, Apache mod_brotli). The saving lands on the assets this host serves, not on the HTML document -- the document's own encoding is reported separately.
Got: www.fabioantichi.it (text/css)
Warning::
!
fonts.googleapis.com serves text assets uncompressed (assets: 6)
The sampled response carries a text content type but no Content-Encoding, so the bytes go over the wire raw. Text compression typically removes 70-80% of a JS or CSS payload -- this is the single cheapest transfer win available on this host.
Got: fonts.googleapis.com (text/css)
Info::
✓
s.w.org serves assets with brotli (assets: 6)
Got: s.w.org (image/svg+xml)
Info::
✓
www.googletagmanager.com serves assets with brotli (assets: 3)
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.
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+
JS Execution Cost
394ms total JS execution
PASS
394ms total JS execution
Info::
i
https://www.fabioantichi.it/: 163ms CPU time
Info::
i
https://www.googletagmanager.com/gtag/js?id=GT-WB7...: 104ms CPU time
Info::
i
Unattributable: 69ms CPU time
Info::
i
https://cdn.iubenda.com/cookie_solution/iubenda_cs...: 58ms CPU time
3 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
3
146 KB total
Render-blocking
0
of 3
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
UcC73FwrK3iLTeHuS_nVMrM...woff2swap
Size47 KB
Load time86 ms
Start1.5 s
RiskFOUT — text flashes from fallback to web font
92zatBhPNqw73oTd4jQmfxI...woff2swap
Size26 KB
Load time73 ms
Start1.5 s
RiskFOUT — text flashes from fallback to web font
Wnz6HAc5bAfYB2Q7ZjYYiAz...woff2swap
Size73 KB
Load time97 ms
Start1.5 s
RiskFOUT — text flashes from fallback to web font
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)
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+
HTTP/3 (QUIC)
HTTP/3 advertised via Alt-Svc
PASS
HTTP/3 advertised via Alt-Svc
Info::
✓
HTTP/3 (QUIC) is supported
First-load mobile users on cellular networks see meaningful latency improvements with HTTP/3. The QUIC transport collapses TLS + TCP handshakes into one and recovers faster from packet loss.
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.
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Aruba.it
Network Waterfall
73 requests over 2364ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
82%of JavaScript execution is third-party
First-party Third-party325ms · 309KB · €2/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
www.fabioantichi.it
www.fabioantichi.it
Other
163ms
13 KB
—
€1/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
104ms
182 KB
32%
€1/mo
Optional
Iubenda
cdn.iubenda.com
Consent
58ms
113 KB
50%
€0/mo
Essential
www.fabioantichi.it
Other
Optional
Execution163ms
Transfer13 KB
Monthly Cost€1/mo
Google Tag Manager
Tag Manager
Optional
Execution104ms
Transfer182 KB
Unused32%
Monthly Cost€1/mo
Iubenda
Consent
Essential
Execution58ms
Transfer113 KB
Unused50%
Monthly Cost€0/mo
82% 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
50% of Iubenda'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.
