Core Web Vitals Checker

Test your website's performance on mobile and desktop

Free tool powered by PageSpeed Insights API • Compare devices side-by-side

Free Performance Testing Tool — This tool provides performance estimates for informational purposes only. Results may vary based on network conditions and testing methodology. Always verify with multiple tools and consult professionals before making critical decisions. Learn more

What are Core Web Vitals?

Core Web Vitals are a set of specific metrics that Google uses to measure user experience on the web. They're part of Google's page experience signals used to rank search results.

LCP

Largest Contentful Paint

Measures loading performance. Should occur within 2.5 seconds.

FID

First Input Delay

Measures interactivity. Should be less than 100 milliseconds.

CLS

Cumulative Layout Shift

Measures visual stability. Should maintain a score below 0.1.

AI Performance Advisor

Get intelligent, personalized recommendations powered by AI. Ask questions and get expert advice on improving your Core Web Vitals.

Available after your first test

Compare Competitors

Benchmark your site against up to 5 competitors. See who wins on LCP, FID, and CLS side-by-side.

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Track Over Time

All your tests are automatically saved. View historical trends and track performance improvements.

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