Core Web Vitals (CWV) are the speed metrics part of Google’s Page Experience signals used to measure user experience. The metrics measure visual load with Largest Contentful Paint (LCP), visual stability with Cumulative Layout Shift (CLS), and interactivity with First Input Delay (FID). We wanted to look at the data to see how websites were doing and if we could glean any important insights. The data we used is from the Chrome User Experience Report (CrUX), which is the source of Core Web Vitals data and is data from actual Chrome users. In the public dataset, the data is aggregated at the origin (domain) level.
We also wanted
To look at page-level data, so we pulled over 5.2M pages with Vitals information in Ahrefs’ Site Audit. Websites seem to struggle a bit more with LCP on executive data mobile compared to desktop. It’s likely because of the connection speed and mobile CPUs having less processing power. For FID, it looks like almost no one needs to worry about this metric on their desktop versions, and very few need to focus on this metric in general. CLS is similar on mobile and desktop. A quick thanks to Oleksiy Golovko for gathering this data from Ahrefs’ Site Audit. He pulled data from 43.66M unique pages. We found only 5.21M (~11.9%) had at least one vitals metric, and 93% of those (or ~4.85M total) had all three metrics. We also noted all of the pages had LCP (99.79%) and CLS (99.91%) metrics.
The metric FID
Was missing the most and only available on 93.08% of pages that had any Vitals metrics. Fewer pages than overall origins (domains) are passing Core UAB Directory Web Vitals (only 21.2% of pages passing). I’m not sure how to account for this fully. I suspect it may be due to caching where secondary page loads tend to be faster. For page-level data, LCP is similar to the origin data. FID is better and something that doesn’t seem to be a concern for most pages. CLS is worse in the page-level data than the origin data. I wanted to study the impact of Core Web Vitals on rankings. But due to the timing of the rollout and other updates that happened at the same time, I don’t think there’s a good method that is conclusive.
