TTFB Test & TTFB Checker
TTFB test and TTFB checker that measures Time to First Byte from multiple locations. See where your server response is slowing things down.
Note: browser tests measure total round-trip from your network. For server-only TTFB use WebPageTest. Three samples are averaged.
How to use the TTFB Test (Time to First Byte)
- 1Paste your URL into the input.
- 2Click Test — the tool samples TTFB multiple times.
- 3Read the average and per-sample timings.
- 4Use the grade to know if your origin is fast enough.
What you can do with the TTFB Test (Time to First Byte)
Measure TTFB on a URL.
Get the millisecond delay between request and first byte from your server.
Test TTFB on WordPress.
Quickly check whether slow PHP/MySQL is dragging your origin response time.
Compare TTFB before and after a change.
Run a baseline test, ship your fix, run again to confirm impact.
Spot CDN vs origin TTFB issues.
Slow TTFB usually means slow origin, missing edge caching, or a far-away region.
TTFB Test (Time to First Byte) FAQs
What's a good TTFB?+
Under 200ms is excellent, under 600ms is acceptable. Google's Core Web Vitals guidance flags TTFB above 800ms.
Why is my TTFB high?+
Most common causes: slow database/backend, no CDN/edge cache, a far origin region, or render-blocking server-side work like uncached WordPress queries.
Do you store the URLs I test?+
No. Each test is a one-shot request, discarded after display.
Does TTFB include DNS and TLS?+
It's measured from the browser's perspective, so it includes connection setup. We average multiple samples to reduce noise.
Will improving TTFB improve my Core Web Vitals?+
Yes — lower TTFB usually pulls LCP and INP down with it, since rendering can't start before the first byte arrives.
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