CrUX
The Chrome User Experience Report, which publishes real-user performance for origins with enough Chrome traffic.
What CrUX does not show
Absence of data is a statement about traffic volume, never about speed.
Where CrUX comes up on this site
- Core Web Vitals without CrUX: field data for small sitesThree sources of Core Web Vitals and what each can tell a small site .t{font:600 13px system-ui,sans-serif;fill:var(--ink)}.s{font:12px…
- Lighthouse scores vary between runs: two runs, 225% apartA site below that threshold can collect its own field data with a first-party beacon; how to measure Core Web Vitals without CrUX walks through it.
- Analytics added 650 ms to every request: how we found itA lab score is one sample from one place; see field data without CrUX and why one Lighthouse run is not a finding .
Related terms in Delivery and rendering
What arrives on the wire, and what only exists after something else runs.
broken embed · payload ratio · render dependence · render dependence gap · edge cache pinning · TTFB · Core Web Vitals · field data · prompt injection · Hydration mismatch · Dynamic rendering · DOM depth · Edge transformation · 202 interstitial · rate limiting · bot management platform
Questions about CrUX
What is CrUX?
The Chrome User Experience Report, which publishes real-user performance for origins with enough Chrome traffic.
What does CrUX not show or guarantee?
Absence of data is a statement about traffic volume, never about speed.
Which area of the glossary does CrUX belong to?
Delivery and rendering: What arrives on the wire, and what only exists after something else runs.
← Core Web Vitals · field data →
See it in the full glossary · 772 terms across 19 areas.
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