Core Web Vitals (CWV)
A set of specific factors that Google considers important in a webpage's overall user experience.
Core Web Vitals are a set of real-world, user-centered metrics that Google uses to quantify key aspects of the user experience. They focus on three main areas: loading, interactivity, and visual stability.
The Three Pillars of Core Web Vitals
- Largest Contentful Paint (LCP): Measures loading performance. To provide a good user experience, LCP should occur within 2.5 seconds of when the page first starts loading.
- Interaction to Next Paint (INP): Measures responsiveness. It tracks the time it takes for a page to respond to user interactions like clicks or key presses.
- Cumulative Layout Shift (CLS): Measures visual stability. It quantifies how much the page content shifts unexpectedly during loading.
Improving these metrics is essential for both user satisfaction and search engine rankings.
More on performance
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Related Concepts
LCP (Largest Contentful Paint)
A Core Web Vital that measures when the largest content element on a page becomes visible. Learn what causes slow LCP and how to fix it.
TTFB (Time to First Byte)
What is TTFB? It is the time it takes for a user's browser to receive the first byte of data. Learn how to check TTFB, what causes high TTFB, and how to fix it.
Bounce Rate
The percentage of visitors to a particular website who navigate away from the site after viewing only one page.