About the Core Web Vitals Checker
Core Web Vitals measure loading (Largest Contentful Paint), responsiveness (Interaction to Next Paint) and visual stability (Cumulative Layout Shift). This Core Web Vitals checker runs Google PageSpeed Insights for a public URL and shows field data from the Chrome UX Report: the 75th percentile of real Chrome users over the last 28 days, for both the page and the whole origin.
A page passes when LCP is 2.5 seconds or less, INP 200 milliseconds or less and CLS 0.1 or less. Lighthouse lab metrics and the top opportunities are shown alongside to help diagnose causes. Low-traffic pages may have no page-level field data; in that case the origin data or lab results are your guide. Field data updates daily but reflects a rolling 28 days, so fixes take weeks to show fully.
How to use it
- Enter a public page URL.
- Check the field data for the URL and the whole origin.
- Compare each metric with the good thresholds.
- Use the lab metrics and opportunities to find and fix causes.
Frequently asked questions
Why is there no field data for my page?
Chrome UX Report data is only available when enough real Chrome users visited the page in the last 28 days. Smaller or newer pages often lack page-level data. The origin-level data, which covers your whole domain, may still be available, and lab data from Lighthouse can be used for diagnosis.
Are Core Web Vitals a ranking factor?
Google uses Core Web Vitals as part of its page experience signals. Google has said that good page experience alone does not guarantee top rankings and that relevant, helpful content matters more. Improving vitals is still worthwhile because it benefits real visitors.
I fixed an issue. Why hasn't my score changed?
Field data is a rolling 28-day window, so improvements appear gradually as new visits replace old ones. Lab results change immediately after a fix. Check lab metrics to confirm the fix works, then watch field data over the following weeks.