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Core Web Vitals
Definition
Core Web Vitals are Google's standardized metrics for measuring real-world user experience quality, focusing specifically on loading performance, interactivity, and visual stability.
Also known as: CWV
Explained
Core Web Vitals are Google's standardized metrics for measuring real-world user experience quality, focusing specifically on loading performance, interactivity, and visual stability.
The Three Core Metrics
- Largest Contentful Paint (LCP): Measures loading performance by tracking when the main content element becomes visible. Target: under 2.5 seconds for 75% of page loads.
- First Input Delay (FID): Measures interactivity by calculating the delay between user interaction and browser response. Target: under 100 milliseconds for 75% of interactions.
- Cumulative Layout Shift (CLS): Measures visual stability by quantifying unexpected layout movement during page loading. Target: less than 0.1 for 75% of page loads.
Core Web Vitals connect directly to other essential SEO elements including mobile-first indexing, page experience signals, and SERP positioning. They serve as Google's primary method for measuring the PageRank-equivalent of user experience quality, making them fundamental to modern search success.
Example
Amazon discovered that every 100ms delay in page loading decreased sales by 1%. When they optimized their Core Web Vitals, reducing LCP from 4.2 seconds to 1.8 seconds, they saw a 12% increase in conversion rates and 8% improvement in average order value.