Server response time under 500ms
Your server should return the first byte within 500 milliseconds of the request.
Why time-to-first-byte matters
Time to first byte (TTFB) is how long the crawler waits between sending a request and getting anything back. It is distinct from total page load time — it measures your server, not your assets.
Crawlers allocate a small TTFB budget per request — typically 1 to 2 seconds max, with 500ms as the 'good' threshold. A server that takes 3 seconds to respond is at the edge of the crawler's patience, and one that takes 5 is already being dropped.
How to improve TTFB
- — Serve the HTML from a CDN edge rather than a single origin.
- — Cache rendered pages. If the page does not change per user, it should not be regenerated per request.
- — Use a keepalive connection and HTTP/2 or HTTP/3.
- — Host close to your audience. EU audience, EU hosting.
- — Fix slow database queries in your homepage render path.