Metrics
Time to First Byte (TTFB)
Also: TTFB
The time between request and the first byte of response from the origin or CDN.
Definition
TTFB is what the crawler waits for before any rendering can begin. Good < 800ms. SSG TTFB is whatever the CDN responds in (30-100ms). SSR TTFB depends on origin and data dependencies (200ms-1.5s). Slow TTFB tends to depress crawl rate over time as Google adapts to perceived origin load.
More in Metrics
Largest Contentful Paint (LCP)
The render time of the largest content element visible in the viewport.
Interaction to Next Paint (INP)
Worst-case latency between a user input and the next visual update.
Cumulative Layout Shift (CLS)
How much visible content unexpectedly shifts during a page lifetime.
Time to Interactive (TTI)
The time until the main thread is reliably free to handle user input.
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