Time to First Byte (TTFB): How Fast Your Server Responds
Time to First Byte is the wait between a request and the first byte of the response, covering DNS, connection, and server processing time.
Time to First Byte (TTFB) is how long the browser waits for the first byte from the server.
What It Is
Time to First Byte (TTFB) measures how long a browser waits before the server sends the first byte of the response.
It includes DNS lookup, connection setup, and server processing time.
Why It Matters
- A slow TTFB delays every other performance metric, from FCP to LCP.
- It signals poor hosting, heavy backend work, or slow network routes.
- Visitors perceive server delay as the site being slow.
What Is a Good TTFB
- Under 200 milliseconds is excellent.
- 200 to 500 milliseconds is acceptable for most sites.
- Above 600 milliseconds usually points to a hosting or server problem.
How to Improve
- Switch to faster hosting or use a CDN.
- Use caching so repeat visits skip backend work.
- Optimize database queries and server-side code.
- Use HTTP/2 or HTTP/3 for faster connections.
Before: a slow shared server takes two seconds to start responding.
After: the site moves to fast hosting with a CDN and edge caching.
The result: TTFB drops to a few hundred milliseconds and pages feel instant.
The lesson: the fastest page in the world is useless if the server hesitates.
Quick Tip
Test TTFB from different locations, because a fast server far away can still feel slow to the visitor.
Frequently Asked Questions
Time to First Byte, in Short
Server speed sets the ceiling for page speed.
Fix the backend and every front-end metric follows.