SEO Term Definition
Time to First Byte (TTFB)
The time between a browser requesting a page and receiving the first byte of data from the server.
Reviewed by Alexander Yarovenko · Updated: 2026-07-03
What Is Time to First Byte?
Time to First Byte (TTFB) is a web performance metric that measures the time from when a browser sends an HTTP request to when it receives the first byte of data from the server. It reflects server responsiveness and is a component of Core Web Vitals evaluation.
TTFB Benchmarks
| TTFB | Rating |
|---|---|
| Under 800ms | Good |
| 800ms – 1800ms | Needs Improvement |
| Over 1800ms | Poor |
Factors Affecting TTFB
- Server processing time: Database queries, server-side rendering, application logic
- Network latency: Physical distance between user and server
- DNS lookup time
- TCP/TLS connection establishment
- Caching: Cached responses are served much faster
Improving TTFB
- Use a Content Delivery Network (CDN) to serve content from nodes near users
- Enable server-side caching (Redis, Memcached, full-page cache)
- Optimise database queries and use query caching
- Upgrade hosting to a faster server tier
- Enable HTTP/2 or HTTP/3 on your server