What TTFB includes#
Redirect time, DNS lookup, connection and TLS setup, and the time the server spends generating the page. It isn’t a Core Web Vital, but every millisecond adds directly to FCP and LCP.
Common causes of slow TTFB on WordPress#
- Cheap, overloaded shared hosting or an old PHP version.
- No page caching — every visit rebuilds the page with PHP and database queries.
- Heavy plugins running slow queries on every request.
- Servers far from visitors (e.g. US server for an Indian audience) without a CDN.
- Redirect chains before the page loads.
How to improve it#
- Use quality hosting with PHP 8.x, enough resources and a data centre near your audience.
- Enable full-page caching (server-level or a caching plugin) and object caching (Redis) for dynamic sites.
- Put a CDN in front — Cloudflare can cache full HTML at the edge.
- Find slow plugins with Query Monitor and replace them.
- Remove unnecessary redirects.
Measure TTFB in PageSpeed Insights field data, Chrome DevTools (Network → Timing → “Waiting for server response”) or curl -o /dev/null -s -w "%{time_starttransfer}n" https://example.com/. Related: page speed, CDN explained.