What is the Chrome UX Report (CrUX)? How to see your data

Chrome UX Report (CrUX), explained

Chrome's docs call CrUX the Google dataset of the Web Vitals program. It groups real page loads from Chrome users into page-level and origin-level distributions, split by device, covering the Core Web Vitals plus metrics such as FCP and TTFB. A page passes the Core Web Vitals assessment when the 75th percentile of each metric is good: LCP at 2.5 seconds or less, INP at 200 milliseconds or less, CLS at 0.1 or less.

Not every site gets data. A page or origin must be publicly discoverable (it returns HTTP 200 and isn't noindexed) and popular enough; the minimum isn't published, and you can't submit a URL.

Only some visitors count: Chrome users with usage statistics and history sync switched on, on desktop Chrome or Android Chrome. Chrome on iOS, Android WebView and other Chromium browsers such as Edge are excluded, and Safari isn't Chrome, so iPhone visitors aren't counted. For new or low-traffic sites, PageSpeed Insights falls back to origin-level data and, failing that, shows only lab results, while Search Console's report says "No data available".

Ways in: PageSpeed Insights for a URL or origin, updated daily; Search Console's Core Web Vitals report, which groups similar URLs and lists only indexed ones; CrUX Vis for weekly history; the CrUX API, free and updated daily; and BigQuery, origin-level and released monthly. The older CrUX Dashboard is deprecated in favor of CrUX Vis.

PageSpeed Insights, Search Console's report and the API use a trailing 28-day window, so fixes show up gradually: ship a speed fix today and field numbers keep moving for about four weeks as old visits age out. For faster feedback, add your own real-user monitoring with the web-vitals library, which measures the metrics the way Chrome reports them.

Chrome's docs say Google Search uses CrUX to inform the page experience ranking factor, while Google Search Central says there is no single page experience signal and that Core Web Vitals are used by its ranking systems. Treat CrUX as the measurement, not a score to maximize.

Why it matters for founders

CrUX, not your Lighthouse score, is the real-user data behind Core Web Vitals in PageSpeed Insights and Search Console, and Chrome's docs say Google Search draws on it. Knowing it lags by weeks and needs traffic explains why your reports don't change the day you ship, and why a new site may have nothing to look at yet.

Example

You fix a layout shift on your pricing page. PageSpeed Insights' lab data improves right away, but the CrUX field value takes about four weeks to fall below 0.1 as older visits roll out of the window.

Common mistakes

• Expecting field data to change the day you deploy.
• Assuming a new, low-traffic or noindexed page will have CrUX data.
• Confusing lab scores with field data.
• Treating CrUX as all your visitors. It leaves out Chrome on iOS, Safari, WebView and other browsers.
• Not adding your own real-user monitoring for faster feedback.