What Is TTFB (Time to First Byte) and How to Improve It

Time to First Byte (TTFB) is the time between a browser requesting a page and receiving the first byte of the response. It is the foundation of page speed — nothing else can start until the server responds.

Why TTFB Matters

TTFB directly affects your Largest Contentful Paint (LCP), a Core Web Vitals metric Google uses for ranking. A slow server means a slow LCP no matter how optimized your frontend is.

What Causes a Slow TTFB

1. Slow server / cheap hosting — shared hosting under load.
2. No caching — every request hits the database and rebuilds the page.
3. Distance — the server is far from the user with no CDN.
4. Heavy backend work — unoptimized queries, blocking API calls.
5. No compression / keep-alive — connection overhead per request.

How to Improve TTFB

1. Add a CDN. Cloudflare (free) caches static content at edge locations near your users, cutting network distance dramatically.

2. Cache rendered pages. Serve cached HTML instead of rebuilding on every request:

# Nginx micro-cache example
proxy_cache_path /tmp/cache levels=1:2 keys_zone=micro:10m;
location / {
  proxy_cache micro;
  proxy_cache_valid 200 1m;
}

3. Use static or incremental rendering. In Next.js, prefer static generation or ISR over server rendering for pages that do not change per-request:

export const revalidate = 3600; // regenerate at most hourly

4. Optimize the database. Add indexes for frequent queries, and avoid N+1 queries.

5. Enable compression and keep-alive at the server level (gzip/brotli).

Measure It First

You can measure TTFB in Chrome DevTools → Network → click the document request → Timing tab. Or run your URL through SEO Snapshot — it reports server-measured response time and flags a slow TTFB as a Core Web Vitals risk.