Core Web Vitals (CWV):

A set of three specific Google-defined metrics — Largest Contentful Paint (LCP), Interaction to Next Paint (INP), and Cumulative Layout Shift (CLS) — that measure a webpage's loading speed, interactivity, and visual stability. These, which replaced First Input Delay with INP in 2024, are used by Google as a ranking factor to promote a better user experience.

The Three Pillars of Core Web Vitals (Ideal Scores)

Largest Contentful Paint (LCP - Loading): Measures how fast the main content loads. Ideal: < 2.5 seconds.

Interaction to Next Paint (INP - Interactivity): Measures how quickly a page responds to user inputs. Ideal: < 200 milliseconds.

Cumulative Layout Shift (CLS - Visual Stability): Measures if elements move unexpectedly. Ideal: < 0.1