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.
B
Image Optimization
22 images, 0 KB saveable
REVIEW
22 images, 0 KB saveable
Warning::
!
https://en.altervista.org/images/food_blogger_30_s... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
22images2.5 MB
0oversized-0 KB
21legacy format
1missing 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
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
5 fonts (42 KB)
PASS
5 fonts (42 KB)
Info::
i
5 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
5
42 KB total
Render-blocking
0
of 5
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
pxiEyp8kv8JHgFVrJJfecnF...woff2swap
Size8 KB
Load time24 ms
Start338 ms
RiskFOUT — text flashes from fallback to web font
nKKU-Go6G5tXcr4uPhWnVaF...woff2swap
Size10 KB
Load time27 ms
Start338 ms
RiskFOUT — text flashes from fallback to web font
pxiByp8kv8JHgFVrLEj6Z1x...woff2swap
Size8 KB
Load time26 ms
Start371 ms
RiskFOUT — text flashes from fallback to web font
pxiGyp8kv8JHgFVrJJLucHt...woff2swap
Size8 KB
Load time26 ms
Start371 ms
RiskFOUT — text flashes from fallback to web font
pxiByp8kv8JHgFVrLCz7Z1x...woff2swap
Size8 KB
Load time25 ms
Start418 ms
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
2 hints, 0 missing preconnects
PASS
2 hints, 0 missing preconnects
Info::
✓
Page uses 2 resource hint(s)
Current Resource Hints
preconnect
2
preload—
dns-prefetch—
prefetch—
2 resource hints configured
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
✓
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
Network Waterfall
64 requests over 2727ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100%of JavaScript execution is third-party
First-party Third-party2452ms · 857KB · €39/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
Unattributable
Unattributable
Other
402ms
0 KB
—
€6/mo
Costly
Iubenda
cdn.iubenda.com
Consent
349ms
109 KB
64%
€6/mo
Essential
Google Tag Manager
www.googletagmanager.com
Tag Manager
300ms
167 KB
40%
€5/mo
Costly
en.altervista.org
en.altervista.org
Other
269ms
12 KB
—
€4/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
245ms
151 KB
42%
€4/mo
Costly
en.altervista.org
en.altervista.org
Other
210ms
120 KB
39%
€3/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
201ms
159 KB
51%
€3/mo
Costly
cdn-gl.imrworldwide.com
cdn-gl.imrworldwide.com
Other
151ms
73 KB
54%
€2/mo
Optional
en.altervista.org
en.altervista.org
Other
97ms
1 KB
—
€2/mo
Optional
Iubenda
cdn.iubenda.com
Consent
64ms
2 KB
—
€1/mo
Essential
Google Analytics
www.google-analytics.com
Analytics
60ms
21 KB
—
€1/mo
Optional
cdn-gl.imrworldwide.com
cdn-gl.imrworldwide.com
Other
54ms
7 KB
—
€1/mo
Optional
Iubenda
cdn.iubenda.com
Consent
51ms
36 KB
—
€1/mo
Essential
Unattributable
Other
Costly
Execution402ms
Transfer0 KB
Monthly Cost€6/mo
Iubenda
Consent
Essential
Execution349ms
Transfer109 KB
Unused64%
Monthly Cost€6/mo
Google Tag Manager
Tag Manager
Costly
Execution300ms
Transfer167 KB
Unused40%
Monthly Cost€5/mo
en.altervista.org
Other
Costly
Execution269ms
Transfer12 KB
Monthly Cost€4/mo
Google Tag Manager
Tag Manager
Costly
Execution245ms
Transfer151 KB
Unused42%
Monthly Cost€4/mo
en.altervista.org
Other
Costly
Execution210ms
Transfer120 KB
Unused39%
Monthly Cost€3/mo
Google Tag Manager
Tag Manager
Costly
Execution201ms
Transfer159 KB
Unused51%
Monthly Cost€3/mo
cdn-gl.imrworldwide.com
Other
Optional
Execution151ms
Transfer73 KB
Unused54%
Monthly Cost€2/mo
en.altervista.org
Other
Optional
Execution97ms
Transfer1 KB
Monthly Cost€2/mo
Iubenda
Consent
Essential
Execution64ms
Transfer2 KB
Monthly Cost€1/mo
Google Analytics
Analytics
Optional
Execution60ms
Transfer21 KB
Monthly Cost€1/mo
cdn-gl.imrworldwide.com
Other
Optional
Execution54ms
Transfer7 KB
Monthly Cost€1/mo
Iubenda
Consent
Essential
Execution51ms
Transfer36 KB
Monthly Cost€1/mo
These scripts may cost more than they're worth
Unattributable adds 402ms and costs ~€6/month
Google Tag Manager adds 300ms and costs ~€5/month
en.altervista.org adds 269ms and costs ~€4/month
Google Tag Manager adds 245ms and costs ~€4/month
en.altervista.org adds 210ms and costs ~€3/month
Google Tag Manager adds 201ms and costs ~€3/month
100% 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
Unattributable takes 402ms 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
64% 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.
Source: web.dev
Google Tag Manager takes 300ms 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
en.altervista.org takes 269ms 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
Google Tag Manager takes 245ms 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
en.altervista.org takes 210ms 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
Google Tag Manager takes 201ms 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
51% of Google Tag Manager'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
54% of cdn-gl.imrworldwide.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.