Cumulative Layout Shift

Cumulative Layout Shift, or CLS, is one of the three Core Web Vitals. It measures how much the content of a page moves around unexpectedly while it loads, such as text jumping down when an image or an advert appears above it. Google calls a score of 0.1 or less good. Giving every image its width and height fixes most of it. See our Core Web Vitals guide for writers.