Server response time is measured independently from page load time. Confusing the two leads to misdiagnosed pe

Server response time is measured independently from page load time. Confusing the two leads to misdiagnosed performance problems.

Time to First Byte (TTFB) is the time between a browser sending a request and receiving the first byte of the response from the server. It isolates server-side performance.

A high TTFB (above 600ms) points to:
- Slow server/underpowered hosting
- Unoptimized database queries
- PHP/Python/Node processing overhead
- Missing server-side caching
- Geographic distance between server and visitor

A normal TTFB but slow overall load points to:
- Large page assets (images, scripts, stylesheets)
- Too many HTTP requests
- No browser caching headers
- Render-blocking resources

Measure TTFB specifically using GTmetrix's waterfall chart, WebPageTest.org, or Chrome DevTools Network panel. Filter for the main document request and check the TTFB column.

Fixing the wrong layer is a common mistake — optimize your server before your assets, or the asset optimization won't move the needle.