Time To First Byte (TTFB)
Measures the server's response time to the first byte.
What is this check?
TTFB measures how long it takes for a browser to receive the first byte of data from your server after making a request. It's a measure of server responsiveness.
Why is it important?
A fast TTFB is a sign of a healthy and well-optimized server. A slow TTFB means users are waiting longer for anything to even start appearing on their screen.
What is the impact?
A high TTFB directly leads to slower page load times and a poor user experience. Google considers it an important metric for page experience.