TTFB (Time to First Byte)

What is TTFB (Time to First Byte)?

TTFB (Time to First Byte) is the time between a browser requesting a page and the first byte of the response arriving. The value shows how quickly a server responds. TTFB is not a Core Web Vital, but it is a useful diagnostic metric for page speed.

Why is TTFB important?

• The base of all speed: a slow server response also delays LCP and other loading milestones.
• Points to server issues: a high TTFB often comes from hosting, missing caching or heavy plugins.
• Clear guideline: Google’s web.dev treats 0.8 seconds or less as good.

Examples of TTFB

• A cached page served through a CDN: TTFB well under 0.8 seconds
• A store on slow hosting without caching: TTFB far above 1.8 seconds, which web.dev rates as poor
• You can measure it with PageSpeed Insights or the Network tab in Chrome

How do you improve TTFB?

Improve TTFB with better hosting, page caching, a CDN and fewer heavy database queries or plugins. Then test again on several pages (technical SEO).