What is Time to First Byte?
Also called: TTFB
The short answer
Time to First Byte is how long the browser waits after requesting a page before the first byte of the response arrives; it reflects server and network speed.
Time to First Byte, explained
Static pages on a CDN usually have low TTFB; slow databases, cold servers and distant origins raise it.
Questions people ask about Time to First Byte
What is Time to First Byte?
Time to First Byte is how long the browser waits after requesting a page before the first byte of the response arrives; it reflects server and network speed.
Related terms
A CDN is a network of servers around the world that keeps copies of a site's files and serves each visitor from the location nearest to them.
Edge functionsEdge functions are small pieces of server code that run in data centres close to each visitor, so dynamic responses arrive with minimal delay.
Largest Contentful PaintLargest Contentful Paint measures how long it takes for the largest visible element, usually the hero image or headline, to appear; good is 2.5 seconds or less.
Page speedPage speed is how quickly a web page loads and becomes usable, measured by metrics like Largest Contentful Paint, Interaction to Next Paint and layout stability.
Part of the Web Encyclopedia by Apex Flow Digital. Definitions are general knowledge, kept current, with no invented statistics.