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Core Web Vitals

Google's three metrics for real-world page experience: LCP (loading), INP (responsiveness) and CLS (visual stability).

Definition

Core Web Vitals are Google's standardized metrics for page experience, measured from real Chrome users: LCP (Largest Contentful Paint), INP (Interaction to Next Paint) and CLS (Cumulative Layout Shift). Each has a target that must be met for at least 75% of page loads.

The targets

LCP under 2.5 seconds — loading. INP under 200 milliseconds — responsiveness to taps and clicks. CLS under 0.1 — visual stability. Images are the leading cause of failures in all three: the hero image usually is the LCP element, decoding blocks INP, and missing width/height attributes cause CLS.

Related guides

Images & Core Web VitalsImage optimization guideWhat is LCP?

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Frequently asked questions

LCP (Largest Contentful Paint) measures loading, INP (Interaction to Next Paint) measures responsiveness to user input, and CLS (Cumulative Layout Shift) measures visual stability. Each must meet its target for at least 75% of page loads.

Under 2.5 seconds for at least 75% of page loads. On most pages the LCP element is a hero image, so compressing it, converting it to AVIF or WebP, and adding fetchpriority="high" plus a preload are the highest-impact fixes.

Yes. Page speed is a confirmed Google ranking signal and Core Web Vitals are part of that signal. Google measures them from real users via the Chrome UX Report, and poor scores can also limit eligibility for certain rich results.