Metrics
Core Web Vitals
Google's headline page-experience metrics: LCP, INP, CLS.
Definition
A standardized set of Real User Metrics (RUM) Google publishes via the Chrome User Experience Report (CrUX). Currently Largest Contentful Paint (loading), Interaction to Next Paint (responsiveness, replaced FID in 2024), and Cumulative Layout Shift (visual stability). A weak input to ranking but a strong input to user satisfaction.
See also
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 First Byte (TTFB)
The time between request and the first byte of response from the origin or CDN.
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