Hostilla.pl IT glossary
What is TTFB?
TTFB, i.e. Time To First Byte, is the time from sending the request by the browser to receiving the first byte of the response from the server. A high TTFB may be due to slow PHP, database, lack of cache, external APIs or load. Diagnosis starts with cache, logs, PHP X-Ray and tests without plugins.
Definition
TTFB, i.e. Time To First Byte, is the time from sending the request by the browser to receiving the first byte of the response from the server. A high TTFB may be due to slow PHP, database, lack of cache, external APIs or load. Diagnosis starts with cache, logs, PHP X-Ray and tests without plugins.
What does it mean in practice?
For websites and online services, TTFB affects response time, reliability, resource usage and the quality of the network path.
A practical Hostilla.pl example
Measure the same URL from a repeatable location before and after a change. TTFB should be correlated with server response time, application logs, resource use, caching and the network path rather than judged from one browser refresh.
What should you check?
- the exact URL, device, location and test time
- a baseline for response time and page metrics
- PHP, database, disk, cache and resource usage
- one controlled change followed by the same test