Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
95
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
66
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
1.45 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.51 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
0 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.023
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.45 s
Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.
1.51 s
Page Load Progression
476 ms
952 ms
1.4 s
1.9 s
2.4 s
2.9 s
3.3 s
3.8 s
Checks
22
10 PASS8 REVIEW1 FIX
F
Page Weight Budget
Action
3.5 MB transferred, 39 requests
FIX
3.5 MB transferred, 39 requests
Warning::
!
Page weighs 5.5 MB (3.5 MB transferred)
Warning::
!
Images are 2.7 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 2.7 MB
Warning::
!
JavaScript is 671 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 671 KB
Info::
✓
39 HTTP requests
Info::
i
Estimated 0.73 g CO2 per page load
3.5 MBtransferred
39 requests
0.73 g CO2 per page load
Images2.7 MiB78%
JavaScript671.0 KiB19%
Fonts90.6 KiB3%
HTML27.7 KiB1%
CSS2.0 KiB0%
Other803 B0%
Other780 B0%
Other46 B0%
02.4 MB4.9 MB
Over budget
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Why this matters
Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.
Source: web.dev
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
15 images, 0 KB saveable
REVIEW
15 images, 0 KB saveable
Info::
✓
All images are well-optimized
15images2.7 MB
0oversized-0 KB
14legacy format
0missing dimensionsCLS risk
B
JS Execution Cost
695ms total JS execution
REVIEW
695ms total JS execution
Warning::
!
https://ttmb-coffee.surge.sh/: 629ms CPU time
Info::
i
Unattributable: 66ms CPU time
Main Thread Breakdown
Script Evaluation 38% Other 31% Style & Layout 21%
Script
Total
Scripting
Parse/Compile
Party
https://ttmb-coffee.surge.sh/
629ms
246ms
2ms
1st
Unattributable
66ms
2ms
0ms
1st
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.
B
Document Compression
Document response uses gzip; brotli would be ~20% smaller
REVIEW
Document response uses gzip; brotli would be ~20% smaller
Info::
i
Main HTML response uses gzip (brotli would be ~20% smaller)
All current browsers support brotli. Most CDNs (Cloudflare, Fastly, AWS CloudFront, Vercel, Netlify) can switch from gzip to brotli with a single config flag. Origin servers (nginx, Apache) need a brotli module compiled in -- nginx-brotli or Apache mod_brotli.
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.
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=0 (≤ 5min) is appropriate
PASS
Main HTML max-age=0 (≤ 5min) is appropriate
Info::
✓
Main HTML max-age=0 (≤ 5min) is appropriate
Got: public, max-age=0, must-revalidate
A+
Server Response Intelligence
2 server-response signal(s) detected
PASS
2 server-response signal(s) detected
Info::
✓
`Vary` header declared: Accept-Encoding
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::
✓
`ETag` present -- conditional GET supported
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
39 requests over 1522ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Image Optimization
65 images, 3549 KB total, 2521 KB wasted
INFO
Image Optimization Audit
Total Images
65
Total Size
3549 KB
Oversized
6
Wasted
2521 KB
65 missing dimensions9 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.