What do real users experience on your site?
Core Web Vitals are measured from real Chrome users, not a lab. This reads Google's Chrome UX Report for your origin and reports the p75 of LCP, CLS and INP — the field data Google actually uses.
Queries Google's Chrome UX Report for your origin. No page is fetched and nothing is stored.
How this check works
Shipwork asks Google's Chrome UX Report API for the field metrics of your origin — the 75th percentile of Largest Contentful Paint, Cumulative Layout Shift and Interaction to Next Paint, measured from real Chrome users over the last 28 days. It reports which metric is failing and by how much. Origins with too little traffic have no CrUX data, and the check says so rather than guessing.
Questions
- What is the difference between field and lab data?
- Lab data (Lighthouse) is a single synthetic run. Field data (CrUX) is what real users experienced over 28 days, which is what Google uses for ranking.
- Why does it say no data?
- Google only publishes CrUX data for origins with enough real traffic. A new or low-traffic site has none yet.
- What are good numbers?
- LCP under 2.5s, CLS under 0.1 and INP under 200ms, at the 75th percentile, are the thresholds Google treats as "good".