TTFB distribution
How TTFB is distributed across real-user data, plus pass-rate breakdown.
At a glance the headline numbers for TTFB distribution
How TTFB is distributed across real-user data, plus pass-rate breakdown.
59.0% of sites good on TTFB. The typical site's TTFB is 669ms. The worst 10% are above 1.9s.
The TTFB distribution site count at each TTFB, from good to poor
Most sites are good on TTFB. 59.0% sit at or under 800ms. The typical site is at 669ms, and 75% of sites stay under 1.2s. Only 41.0% miss good TTFB. The slowest 10% are above 1.9s, and the slowest 1% are above 4.1s.
The TTFB pass rate the share of sites that are good, needs improvement and poor
59.0% of sites are good on TTFB. 29.7% are in the needs improvement band, between 800ms and 1.8s. 11.3% are poor, above 1.8s. A miss is usually needs improvement, not poor.
Why this matters for the Core Web Vitals, and where to start fixing it
Time to First Byte is how long the browser waits for the server to start replying. It is a diagnostic metric, not a Core Web Vital, but it is the foundation the others are built on: nothing can render until the first byte arrives, so a slow TTFB pushes back every paint that follows. The causes are on the server and the network, slow backend processing, no caching, or a long trip to a distant origin.
Start by getting a fast, cacheable response out the door. Cache full pages where you can, put a CDN in front so visitors are served from nearby, and keep the backend work on each request small. Early Hints use that wait: the browser can start fetching critical resources while the server is still building the page.
How are sites doing on TTFB?
59.0% of sites have a good TTFB. The typical site sits at 1.2s at the 75th percentile; the slowest 1% pass 4.1s.
212,308 crawled sites with Chrome field data, representing millions of real page loads. How we measured.