Cumulative Layout Shift (CLS)

What is Cumulative Layout Shift (CLS)?

Cumulative Layout Shift (CLS) is a user metric designed to measure unexpected shifts in layout as a page loads.

Cumulative Layout Shift is one of the main Core Web Vitals from by Google which allow developers to benchmark how fast a page is perceived to load for users.

What is a good Cumulative Layout Shift score?

As per the image below, a good CLS score is defined by Google as between 0 and 0.1.

Anything above 0.1 is called as needing improvement, with above 0.25 classed as 'poor'.

Does Cumulative Layout Shift (CLS) affect SEO?

Yes, CLS is one of the primary Core Web Vitals which are now a ranking factor in Google as part of the user experience algorithm.

This means that if you improve your CLS/Core Web Vitals, you will contribute towards better search results.

What are the other Core Web Vitals?

As well as Cumulative Layout Shift, Largest Contentful Paint and First Input Delay are the other two main Core Web Vitals.

Resources

• CLS @ Web.dev

https://www.searchcandy.uk/seo/seo-glossary/core-web-vitals/cumulative-layout-shift/