Understanding and Reducing Time to First Byte (TTFB)

What Is TTFB?

Time to First Byte measures the duration from a client request to receiving the first byte of the response. It includes DNS lookup, TCP connection, TLS handshake, and server processing time.

Measure TTFB

# Using curl
curl -o /dev/null -s -w "DNS: %{time_namelookup}s\nConnect: %{time_connect}s\nTLS: %{time_appconnect}s\nTTFB: %{time_starttransfer}s\nTotal: %{time_total}s\n" https://example.com

Good TTFB Targets

Optimization Strategies

1. Server-Side Caching

# Enable OPcache for PHP
opcache.enable=1
opcache.validate_timestamps=0

# Enable FastCGI cache in Nginx
# Or use Varnish as a full-page cache

2. Database Optimization

• Add indexes on frequently queried columns
• Use query caching (Redis/Memcached)
• Optimize slow queries (check slow query log)

3. TLS Optimization

ssl_session_cache shared:SSL:10m;
ssl_session_timeout 1d;
ssl_session_tickets on;
ssl_stapling on;
ssl_stapling_verify on;

4. Keep-Alive Connections

keepalive_timeout 30;
keepalive_requests 1000;

5. Use a CDN

A CDN caches responses at edge locations worldwide, reducing TTFB for geographically distant visitors.

Monitoring TTFB

• Google PageSpeed Insights
• WebPageTest.org
• Uptime monitoring tools (Uptime Kuma)