Core Web Vitals is Google's set of three user-experience metrics — LCP, INP, and CLS — used as a page-experience ranking signal and as standalone performance quality indicators.
The three metrics in 2026:
- LCP (Largest Contentful Paint): ≤ 2.5s good, ≤ 4.0s needs improvement, > 4.0s poor.
- INP (Interaction to Next Paint): ≤ 200ms good, ≤ 500ms needs improvement, > 500ms poor. INP replaced FID in March 2024.
- CLS (Cumulative Layout Shift): ≤ 0.1 good, ≤ 0.25 needs improvement, > 0.25 poor.
Google scores at the URL level using p75 (75th percentile) over a rolling 28-day window of real-user data from the Chrome User Experience Report (CrUX). A site's overall Core Web Vitals status is the aggregate of its URLs' scores.
Core Web Vitals influences rankings primarily as a tiebreaker between pages of similar content quality. Two PDPs ranking for the same query, with similar content depth and link profiles, will rank in CWV order. CWV also affects conversion directly — 1 second of LCP improvement typically lifts ecommerce conversion 5–15%.