What Are Core Web Vitals?
Core Web Vitals are three Google ranking signals measuring real user experience.
**Quick answer:** LCP measures loading speed (under 2.5s is good), FID measures interactivity (under 100ms), CLS measures layout stability (under 0.1).
LCP — Largest Contentful Paint
Measures how fast your main content loads.
Good: under 2.5 seconds. Poor: over 4 seconds.
Fix by: compressing images, using a CDN, preloading your hero image.
FID — First Input Delay
Measures how fast your page responds to user interaction.
Good: under 100ms. Poor: over 300ms.
Fix by: deferring non-critical JavaScript, removing unused scripts.
CLS — Cumulative Layout Shift
Measures how stable your layout is during loading.
Good: under 0.1. Poor: over 0.25.
Fix by: always setting image dimensions, reserving space for ads.
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