Core Web Vitals are a set of performance metrics defined by Google to measure user experience quality. They focus on three key aspects: loading speed, interactivity, and visual stability. Specifically, these metrics are Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS).
LCP measures how fast the main content appears; FID evaluates how quickly a page responds to user input; CLS tracks layout shifts that can cause elements to move unexpectedly as the page loads. Together, they reflect how smooth and usable a site feels in practice.
Optimizing Core Web Vitals isn’t just about pleasing Google — it’s about respecting your visitors’ time and attention. Techniques like image compression, lazy loading, efficient caching, and streamlined code all contribute to better scores.
Since Google uses these metrics as ranking signals, they bridge technical SEO and user experience. A fast, stable site doesn’t just perform better in search — it keeps people engaged and builds trust.
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