Core Web Vitals (LCP, INP, CLS)
Google's three user-experience metrics for the web: Largest Contentful Paint (loading), Interaction to Next Paint (responsiveness), and Cumulative Layout Shift (visual stability).
Core Web Vitals are the three field metrics Google uses to evaluate page experience for ranking and reporting. LCP (Largest Contentful Paint) measures how quickly the biggest visible element renders, with a good target under 2.5 seconds. INP (Interaction to Next Paint) replaced FID in March 2024 and measures input responsiveness across the page lifetime, good under 200 ms. CLS (Cumulative Layout Shift) measures unexpected visual movement, good under 0.1. Real-user data comes from the Chrome User Experience Report (CrUX), so lab tools like Lighthouse are diagnostic; CrUX is the score that actually drives Search Console.