The Cumulative Layout Shift (CLS) of a webpage is a metric that measures the total of all individual layout shifts and unexpected shifts across the entire lifespan of a webpage. It’s a Core Web Vitals metric, which means it is standardised and reliable for webmasters to use.
The score ranks from 0, which represents a fully static page, upwards by decimal points. The lower the score in this metric, the more stable a layout is regarded to be – which means a better end user experience. In general, CLS scores can be ranked as below:
Good: 0 – 0.1
Needs Improvement: 0.1-0.25
Poor: above 0.25
Our Core Web Vitals Checker can determine what your CLS score is.