Real-user experience over the last 28 days
What this check looks for
This is what real Chrome visitors experienced on ‹scope› over the trailing 28-day window, and whether the site passes Google's Core Web Vitals assessment.
Why it matters
Field data is the only evidence of what your visitors actually get, on their own devices and connections. Search ranking and every public performance report are built on this dataset, not on a lab test.
What it costs your score
This check never deducts. It reports a fact — or reports that something could not be verified — and is shown on the report without moving the score.
- Severity
- info
- Default confidence
- confirmed
- Status when triggered
- info
- Deduction
- 0 points
- Family cap
- none
- Category
- Performance
- Module
- Perf crux
- Fix owned by
- user
- In the ruleset since
- 2026.09
Technical detail
**Data granularity: ‹level›.** ‹level detail›
**Core Web Vitals assessment: ‹assessment›.** Google's assessment passes only when LCP, INP *and* CLS are all in the good band at the 75th percentile. A single metric in the needs-improvement band fails the whole assessment, which is why this line can read "failing" while most of the numbers look reasonable.
‹detail›
Each metric is also reported as a distribution across three buckets — good, needs improvement, poor — so you can see how many of your visits were bad rather than only the percentile. A metric where 20% of visits are poor is a very different site from one where 24% are merely mediocre, even though both may sit in the same band at p75.
The underlying dataset is the Chrome UX Report, published by Google under CC BY 4.0. It covers Chrome users who opted into usage statistics reporting; it is not every visitor, and it excludes other browsers entirely.
Standards and references
Test this on your domain
Run the check that produces this finding, on its own, against any domain.
Other perf crux checks
- The page jumps around while it loads for real visitors
- Real visitors stare at a blank page for too long
- The page is slow to respond when real visitors interact with it
- Not enough real-user traffic for field data
- Real visitors wait too long for the main content to appear
- Real-user performance data was not requested
- Real-user performance data could not be retrieved
- The server takes too long to send the first byte to real visitors