What is the Cumulative Layout Shift (CLS)?

The Cumulative Layout Shift (CLS) concept

Cumulative Layout Shift (CLS) is a measure of website performance. It represents the stability of the layout, calculating each individual change (voluntary or unexpected) that occurs during the existence of the page.

The score is identified as zero if the site is stable and there is no offset. The higher the result, the greater the page layout shift. The fact that page elements are unstable and changing as a user tries to interact with them can negatively impact the user experience.

The CLS is one of Google’s three Core Web Vitals settings, designed to measure the impact of loading times on the user experience of websites.

Core Vitals Web Base Settings also include two other settings: Largest Contentful Paint (LCP) and First Input Delay (FID).

Updated on: 23/03/2023