performance · Reference
Core Web Vitals
Published by web.dev (Google) · Free · Official
The official definitions of the speed and stability metrics Google uses to evaluate real-world page experience.
Why it matters
Optimizing blind wastes effort — these definitions tell you exactly what is measured, at what thresholds.
What it helps with
- Understanding LCP, INP and CLS precisely
- Choosing the right metric to optimize for each page type
Hosted by web.dev (Google). Rankly describes this resource but does not reproduce its content.
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