Performance metric
What is TTFB?
Time to First Byte measures how long the browser waits before it receives the first byte from the server. It includes redirects, connection setup, server work, and CDN behavior.
Plain-English version
How long the server takes to start responding.
Target
Under 800ms
TTFB thresholds
Use thresholds as a triage tool. Field data matters most when there is enough real Chrome traffic for the page.
Good
≤ 800ms
Needs work
800ms–1.8s
Poor
> 1.8s
Why it matters
What a visitor feels when TTFB is bad.
Why TTFB matters
TTFB is the first delay every other loading metric inherits. If the server is slow to answer, LCP and First Contentful Paint often start late too.
What a poor result usually means
A poor TTFB can point to slow hosting, uncached pages, heavy server rendering, database work, slow edge configuration, redirects, or a CDN that is not serving the page close to visitors.
What to fix first
Do not chase the score. Fix the bottleneck.
The right fix depends on the metric, the page template, and whether the issue appears in real visitor data.
- Remove unnecessary redirects before the final page.
- Cache public pages at the CDN or edge when possible.
- Review server rendering, database calls, and plugin overhead.
- Use compression and keep CDN configuration consistent.
- Check whether poor TTFB happens globally or only in specific regions.
How nimo helps
Ask nimo: “What is slowing down my server response time?”
nimo shows whether server response is the main bottleneck or only one part of a larger loading problem.
No signup needed. Takes about 30 seconds.