Cumulative Layout Shift, or CLS, measures unexpected movement of visible page content. It is a score without a time unit. Google’s good threshold is 0.1 or less at the 75th percentile of page loads, assessed separately for mobile and desktop. Source: web.dev: Cumulative Layout Shift

What it might look like on a travel page

As a test scenario, watch a hotel page while its photographs and banners appear. Note whether a price or enquiry button moves just as you try to use it. Record the moving element and what appeared immediately before the movement, so the website team has something concrete to investigate.

Review the whole layout

Try the same page at a narrow mobile width and with a longer room name. These are useful checks because the layout needs to accommodate real content as well as the short text used during design.

Keep a recording or a sequence of screenshots with the test result. Review the changed page again after the fix, including the controls around the moving content, so a local improvement has not hidden an adjacent button.

Written and updated by Travelgenix. Sources checked on 16 October 2026. Worked examples and checklists are editorial illustrations and recommendations, not customer results.