TTFB checker
Measure the Time to First Byte of any URL from multiple global locations — with DNS, connection, server processing and download time broken down for each region.
The metric that tells you if your server is slow
TTFB isolates what your server and network control, before images, fonts and scripts enter the picture. If the first byte takes 900 ms, no amount of front-end optimization will fix the user's perception of a slow site.
This tool measures from real external nodes — the same conditions a user in that region experiences — and splits the total into DNS resolution, connection and TLS, server processing (the pure "backend" time) and body download. High DNS or connect time with low processing time means a network issue; the opposite means your application is the bottleneck.
SiteFlux's performance monitors track TTFB and response times continuously, so you can see regressions after each deploy instead of discovering them in the next Core Web Vitals report.
Frequently asked questions
What is a good TTFB value?
Google's guidance for server response time is under 800 ms for a 'good' experience, with under 200 ms being the ideal target. Anything above 1-2 seconds points to slow backend processing, a cold cache or a server-side redirect chain.
What does TTFB actually measure?
The time from the start of the request until the first byte of the response arrives. It includes DNS resolution, the TCP handshake, the TLS negotiation and the time your server spends generating the page — which is why this tool breaks those phases out separately.
Why is my TTFB different depending on the location?
Physical distance adds latency to every round-trip (DNS, TCP, TLS), and CDNs may serve some regions from cache while others hit the origin. Comparing TTFB across locations shows whether slowness is a global backend problem or a regional network/CDN problem.
How does TTFB relate to Core Web Vitals?
TTFB is the foundation the other metrics are built on: a slow first byte delays Largest Contentful Paint directly. Google does not use TTFB as a ranking signal by itself, but it's the easiest server-side metric to track continuously.
Measured once? SiteFlux tracks TTFB and response times 24/7 from multiple locations and alerts you when your server slows down.
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