Time to First Byte (TTFB): Crawl Audit check 71

Short answer: Time to First Byte (TTFB) is the wait between asking for your page and the first byte of it arriving. Everything else on the page waits for it. Check 71 passes at 0.8 seconds or less, warns up to 1.8 seconds and fails above that, the same bands Google's web.dev uses. TTFB isn't a Core Web Vital itself, but a slow one makes the metrics that are slower too.

What Crawl Audit checks

• If Google has real-user data for your site (the Chrome UX Report), Crawl Audit uses its 75th percentile TTFB.
• Otherwise it uses the time Crawl Audit itself waited for your homepage's first byte. That's one request from one place, so treat it as a rough reading.
• Pass: 800ms or less. Warning: up to 1,800ms. Fail: over 1,800ms.

What Google says

• web.dev: "Good TTFB values are 0.8 seconds or less, and poor values are greater than 1.8 seconds."
• TTFB "precedes every other meaningful user experience metric such as First Contentful Paint (FCP) and Largest Contentful Paint (LCP)."
• "Because TTFB isn't a Core Web Vitals metric, it's not absolutely necessary that sites meet the "good" TTFB threshold, provided that it doesn't impede their ability to score well on the metrics that matter."

TTFB adds up several steps: redirects, the DNS lookup (check 93), connecting and the TLS handshake, then the server building the page.

What usually slows it

• Hosting. web.dev: "Before you even consider other optimization approaches, hosting should be the first thing you consider."
• Distance. A server in one country answering visitors in another. A CDN (check 92) caches pages "on servers that are physically closer to your users."
• Redirects. "One common contributor to a high TTFB is redirects." Each hop is another round trip (check 49).
• Pages built fresh on every visit, with slow database queries or plugins, when they could be cached.

On your platform

• WordPress: a page cache plugin or host-level caching, plus a CDN, is the usual first step.
• Shopify, Wix and Squarespace: the platform runs the servers and CDN, so there's little to change. Keep redirects and heavy apps to a minimum.
• Next.js: prerender pages that don't change per visitor, so the CDN can serve them without running your code.

Sources

• web.dev, Time to First Byte (TTFB) (updated 18 November 2025) and Optimize Time to First Byte (updated 28 November 2025), checked 3 October 2026.