Consider code splitting or tree shaking to reduce unused code.
Why this matters
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.
Why this matters
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.
Why this matters
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
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+
Page Weight Budget
495 KB transferred, 50 requests
PASS
495 KB transferred, 50 requests
Info::
✓
Page weighs 1.9 MB (495 KB transferred)
Info::
✓
50 HTTP requests
Info::
i
Estimated 0.10 g CO2 per page load
495 KBtransferred
50 requests
0.10 g CO2 per page load
JavaScript380.2 KiB77%
Fonts42.1 KiB9%
HTML32.0 KiB6%
Images19.0 KiB4%
CSS17.7 KiB4%
Other3.1 KiB1%
Other711 B0%
Other168 B0%
02.4 MB4.9 MB
Under budget
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
Image Optimization
11 images, 0 KB saveable
PASS
11 images, 0 KB saveable
Info::
✓
All images are well-optimized
11images15 KB
0oversized-0 KB
2legacy format
0missing dimensionsCLS risk
A+
Font Loading
1 fonts (42 KB)
PASS
1 fonts (42 KB)
Info::
i
1 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
1
42 KB total
Render-blocking
0
of 1
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
memvYaGs126MiZpBA-UvWbX...woff2swap
Size42 KB
Load time88 ms
Start5.1 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+
Document Compression
Document response uses brotli
PASS
Document response uses brotli
Info::
✓
Main HTML response uses brotli (Content-Encoding: br)
Brotli is the best text-compression algorithm for general use, ~20% smaller than gzip on average (40% on smaller files). Modern browsers all support it.
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
The page declares a `Vary` header, telling downstream caches which request headers the response varies on. Critical for content-negotiated responses (compression, language, cookies, device class).
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.
2 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.
A+
CSS Performance Depth
No CSS performance depth issues detected
PASS
No CSS performance depth issues detected
Info::
✓
No CSS performance depth issues detected
Asset Compression
No text asset hosts to measure
INFO
No text asset hosts to measure
Info::
i
No third-party or subdomain host served enough text assets to measure
Asset compression is measured per host, from one HEAD request against a sampled resource. Pages that serve all their JS and CSS from the document's own origin are covered by the document compression check instead.
Network Waterfall
50 requests over 5361ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
43%of JavaScript execution is third-party
First-party Third-party909ms · 362KB · $12/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
fundingchoicesmessages.google.com
fundingchoicesmessages.google.com
Other
276ms
72 KB
50%
$4/mo
Costly
fundingchoicesmessages.google.com
fundingchoicesmessages.google.com
Other
268ms
71 KB
—
$4/mo
Costly
pagead2.googlesyndication.com
pagead2.googlesyndication.com
Other
217ms
163 KB
80%
$3/mo
Costly
pagead2.googlesyndication.com
pagead2.googlesyndication.com
Other
148ms
56 KB
38%
$2/mo
Optional
fundingchoicesmessages.google.com
Other
Costly
Execution276ms
Transfer72 KB
Unused50%
Monthly Cost$4/mo
fundingchoicesmessages.google.com
Other
Costly
Execution268ms
Transfer71 KB
Monthly Cost$4/mo
pagead2.googlesyndication.com
Other
Costly
Execution217ms
Transfer163 KB
Unused80%
Monthly Cost$3/mo
pagead2.googlesyndication.com
Other
Optional
Execution148ms
Transfer56 KB
Unused38%
Monthly Cost$2/mo
These scripts may cost more than they're worth
fundingchoicesmessages.google.com adds 276ms and costs ~$4/month
fundingchoicesmessages.google.com adds 268ms and costs ~$4/month
pagead2.googlesyndication.com adds 217ms and costs ~$3/month
43% of JavaScript execution time comes from third-party scripts.
Why this matters
Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.
Learn more ▾▴
Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.
Source: web.dev / HTTP Archive Web Almanac
fundingchoicesmessages.google.com takes 276ms 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
50% of fundingchoicesmessages.google.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
fundingchoicesmessages.google.com takes 268ms 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
pagead2.googlesyndication.com takes 217ms 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
80% of pagead2.googlesyndication.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.