CLS distribution
How CLS is distributed across real-user data, plus pass-rate breakdown.
At a glance the headline numbers for CLS distribution
How CLS is distributed across real-user data, plus pass-rate breakdown.
0.0% of sites pass CLS. The typical site's CLS is —. The worst 10% are above —.
CLS Distribution the value at each percentile across all sites
Why this matters for the Core Web Vitals, and where to start fixing it
Cumulative Layout Shift measures how much the page moves around while it loads. A button jumps just as someone goes to tap it, an ad pushes the article down, the text reflows when a late font arrives. Every one of those is a layout shift, and they add up into a score that reflects how stable the page feels. Unlike the other vitals, CLS is rarely about speed and almost always about reserving space.
Start by giving everything that loads late a place to land. Set width and height on images and video so the browser reserves the box before the file arrives. Reserve space for ads, embeds and banners instead of letting them push content. Load fonts so the fallback and the web font take the same room, and keep animations on transform rather than properties that trigger layout.
Chrome field data from 189,915 sites, representing millions of real page loads. How we measured.