Site Speed Check
Enter any website URL to measure its delivery performance — TTFB, payload, compression and caching — and get a prioritised list of concrete fixes.
Recommendations
What it checks
- Time to First Byte (TTFB) — how long the server takes to start responding. High TTFB points at slow backend processing or a distant origin with no edge caching.
- Payload & compression — the document's transfer size and whether Brotli/gzip is enabled. Text compression typically cuts transfer by 60–80%.
- Caching headers — whether
Cache-Controlsets a sensiblemax-ageso repeat visits and CDNs can serve from cache. - Render-blocking resources — scripts in the
<head>withoutasync/defer, and excessive stylesheet requests, that delay first paint. - Mobile readiness — a responsive
viewportmeta tag and image lazy-loading. - Transport security — HTTPS and HSTS.
How the score works
The score starts at 100 and deducts weighted points per finding (high-severity issues cost the most), with additional penalties for slow TTFB and total time. It's a directional health indicator, not a lab-grade Core Web Vitals measurement — for field data, pair it with real-user monitoring (see our article on synthetic vs real-user monitoring) and with performance budgets in CI.
A note on privacy
The URL you enter is fetched once, server-side, to analyse it. Nothing is stored. Internal and private addresses are blocked.
Comments are powered by Giscus (GitHub Discussions). Enable them by
configuring GISCUS in src/consts.ts — see
giscus.app.