data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADAA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADAA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADAA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/gif;base64,R0lGODlhAwACAIAAAP///wAAACH5... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
21images608 KB
0oversized-0 KB
10legacy format
4missing 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
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
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.
B
JavaScript Blocking
2 JS blocking issue(s) detected
REVIEW
2 JS blocking issue(s) detected
Warning::
!
10 render-blocking <script src> tag(s) without async/defer
Each `<script src=...>` without `async`, `defer`, or `type="module"` blocks HTML parsing while the browser fetches and executes it. The block lasts the entire round-trip + execution time -- on slow networks this translates directly into LCP delay. Add `defer` (executes after parse, in source order) for scripts that interact with the DOM, or `async` (executes whenever ready) for analytics / independent scripts. Module scripts (`type="module"`) are deferred by default.
Warning::
!
Total JS execution time is 5.4 s -- over the 3.5s budget
Total JavaScript execution (parse + compile + run) across all scripts exceeds 3.5 seconds. On low-end devices that becomes 7-15+ seconds and shows up directly in TBT and INP. Reduce by: tree-shaking unused dependencies, code-splitting (dynamic `import()`), removing or deferring third-party tracking, and replacing heavy frameworks where they're not needed.
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 (212 KB)
PASS
7 fonts (212 KB)
Info::
i
7 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
7
212 KB total
Render-blocking
0
of 7
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
dm-sans-v6-latin-ext_la...woff2swap
Size23 KB
Load time6 ms
Start276 ms
RiskFOUT — text flashes from fallback to web font
conad-corporate-icons.ttfttfswap
Size62 KB
Load time8 ms
Start276 ms
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
dm-sans-v6-latin-ext_la...woff2swap
Size23 KB
Load time27 ms
Start278 ms
RiskFOUT — text flashes from fallback to web font
dm-sans-v6-latin-ext_la...woff2swap
Size23 KB
Load time31 ms
Start278 ms
RiskFOUT — text flashes from fallback to web font
roboto-slab-v13-latin-e...woff2swap
Size23 KB
Load time13 ms
Start278 ms
RiskFOUT — text flashes from fallback to web font
dm-sans-v6-latin-ext_la...woff2swap
Size24 KB
Load time22 ms
Start279 ms
RiskFOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a...woff2swap
Size34 KB
Load time143 ms
Start1.3 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)
Fixing the unchecked items could save ~19 KB and ~38 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+
Main HTML Cache-Control
Main HTML max-age=300 (≤ 5min) is appropriate
PASS
Main HTML max-age=300 (≤ 5min) is appropriate
Info::
✓
Main HTML max-age=300 (≤ 5min) is appropriate
Got: max-age=300
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+
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
A+
CSS Performance Depth
No CSS performance depth issues detected
PASS
No CSS performance depth issues detected
Info::
✓
No CSS performance depth issues detected
A
HTTP Caching
max-age=300 (5 minutes)
PASS
max-age=300 (5 minutes)
Info::
✓
Cache-Control header is set
Got: max-age=300
Info::
✓
Effective TTL: 5 minutes (max-age=300)
Info::
i
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control
max-age=300
Directive
Value
Meaning
max-age
300
Cache for 5 minutes
Effective TTL: 300 seconds
Network Waterfall
77 requests over 1530ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
92%of JavaScript execution is third-party
First-party Third-party4985ms · 1105KB · €26/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
www.gstatic.com
www.gstatic.com
Other
845ms
0 KB
49%
€4/mo
Costly
www.conad.it
www.conad.it
Other
789ms
38 KB
64%
€4/mo
Costly
www.conad.it
www.conad.it
Other
779ms
168 KB
74%
€4/mo
Costly
www.conad.it
www.conad.it
Other
536ms
41 KB
—
€3/mo
Costly
acsbapp.com
acsbapp.com
Other
470ms
224 KB
53%
€2/mo
Costly
assets.adobedtm.com
assets.adobedtm.com
Other
337ms
110 KB
37%
€2/mo
Costly
www.conad.it
www.conad.it
Other
304ms
7 KB
—
€2/mo
Costly
www.conad.it
www.conad.it
Other
295ms
5 KB
—
€2/mo
Costly
maps.googleapis.com
maps.googleapis.com
Other
158ms
83 KB
64%
€1/mo
Optional
Facebook Pixel
connect.facebook.net
Advertising
144ms
98 KB
44%
€1/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
141ms
126 KB
52%
€1/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
110ms
151 KB
41%
€1/mo
Optional
Facebook Pixel
connect.facebook.net
Advertising
77ms
54 KB
45%
€0/mo
Optional
www.gstatic.com
Other
Costly
Execution845ms
Transfer0 KB
Unused49%
Monthly Cost€4/mo
www.conad.it
Other
Costly
Execution789ms
Transfer38 KB
Unused64%
Monthly Cost€4/mo
www.conad.it
Other
Costly
Execution779ms
Transfer168 KB
Unused74%
Monthly Cost€4/mo
www.conad.it
Other
Costly
Execution536ms
Transfer41 KB
Monthly Cost€3/mo
acsbapp.com
Other
Costly
Execution470ms
Transfer224 KB
Unused53%
Monthly Cost€2/mo
assets.adobedtm.com
Other
Costly
Execution337ms
Transfer110 KB
Unused37%
Monthly Cost€2/mo
www.conad.it
Other
Costly
Execution304ms
Transfer7 KB
Monthly Cost€2/mo
www.conad.it
Other
Costly
Execution295ms
Transfer5 KB
Monthly Cost€2/mo
maps.googleapis.com
Other
Optional
Execution158ms
Transfer83 KB
Unused64%
Monthly Cost€1/mo
Facebook Pixel
Advertising
Optional
Execution144ms
Transfer98 KB
Unused44%
Monthly Cost€1/mo
Google Tag Manager
Tag Manager
Optional
Execution141ms
Transfer126 KB
Unused52%
Monthly Cost€1/mo
Google Tag Manager
Tag Manager
Optional
Execution110ms
Transfer151 KB
Unused41%
Monthly Cost€1/mo
Facebook Pixel
Advertising
Optional
Execution77ms
Transfer54 KB
Unused45%
Monthly Cost€0/mo
These scripts may cost more than they're worth
www.gstatic.com adds 845ms and costs ~€4/month
www.conad.it adds 789ms and costs ~€4/month
www.conad.it adds 779ms and costs ~€4/month
www.conad.it adds 536ms and costs ~€3/month
acsbapp.com adds 470ms and costs ~€2/month
assets.adobedtm.com adds 337ms and costs ~€2/month
www.conad.it adds 304ms and costs ~€2/month
www.conad.it adds 295ms and costs ~€2/month
92% 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.gstatic.com takes 845ms 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.conad.it takes 789ms 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 www.conad.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.conad.it takes 779ms 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
74% of www.conad.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.conad.it takes 536ms 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
acsbapp.com takes 470ms 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
53% of acsbapp.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
assets.adobedtm.com takes 337ms 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.conad.it takes 304ms 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.conad.it takes 295ms 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 maps.googleapis.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
52% 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.