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Performance

What is Server Response Time?

The time it takes for a server to respond to a request from a browser, measured from request initiation to receiving the first byte of response.

Server response time measures how long your server takes to process a request and start sending a response. It's closely related to Time to First Byte (TTFB).

What affects server response time

Server-side factors

  • Database query performance
  • Server-side code efficiency
  • Server hardware/resources
  • Application architecture

Network factors

  • Distance to server
  • Network congestion
  • DNS resolution time
  • TLS negotiation

Measuring server response time

Tools to measure:

  • Browser DevTools (Network tab)
  • Lighthouse
  • WebPageTest
  • VitalSentinel

Improving server response time

  1. Optimize database queries
  2. Implement caching layers
  3. Use a CDN
  4. Upgrade server hardware
  5. Optimize server-side code
  6. Use efficient hosting

Target values

  • Good: Under 200ms
  • Acceptable: 200-600ms
  • Slow: Over 600ms

Monitor your website performance

VitalSentinel tracks Core Web Vitals and performance metrics to help you stay ahead of issues.