Cumulative Layout Shift (CLS) is too high: what it is, why it matters, and how to fix it
The Cumulative Layout Shift — how much visible content unexpectedly moves while the page loads — exceeds Google's threshold. Good is 0.1 or under; over 0.25 is poor.
Where this fits: performance in SEO
Why cumulative layout shift (cls) is too high hurts your rankings
CLS is one of the three Core Web Vitals and a Google ranking signal. Content that jumps as images, ads, or fonts load causes mis-taps (e.g. hitting the wrong button) and a jarring experience. Google demotes pages that shift unexpectedly.
This is a high-severity issue: it directly suppresses rankings or click-through on the pages it affects. It belongs in your current sprint, prioritised by how many pages carry it.
How to fix it
Reserve space for anything that loads asynchronously: set explicit width/height or CSS aspect-ratio on images, iframes, and ad slots; never insert content above existing content once the page is visible; and preload web fonts while using font-display: optional or swap to avoid late reflow.
<!-- Reserve the image box so later loading causes no shift -->
<img src="photo.jpg" alt="…" width="1200" height="675" style="max-width:100%;height:auto" />Frequently asked questions
What does "Cumulative Layout Shift (CLS) is too high" mean?
The Cumulative Layout Shift — how much visible content unexpectedly moves while the page loads — exceeds Google's threshold. Good is 0.1 or under; over 0.25 is poor.
Why does cumulative layout shift (cls) is too high matter for SEO?
CLS is one of the three Core Web Vitals and a Google ranking signal. Content that jumps as images, ads, or fonts load causes mis-taps (e.g. hitting the wrong button) and a jarring experience. Google demotes pages that shift unexpectedly.
How do I fix cumulative layout shift (cls) is too high?
Reserve space for anything that loads asynchronously: set explicit width/height or CSS aspect-ratio on images, iframes, and ad slots; never insert content above existing content once the page is visible; and preload web fonts while using font-display: optional or swap to avoid late reflow.
How serious is this issue?
This is a high-severity issue: it directly suppresses rankings or click-through on the pages it affects. It belongs in your current sprint, prioritised by how many pages carry it. It belongs to the performance family of checks.
How do I find every page affected by this on my site?
Run a free Dr Urls audit: it crawls your site, detects cumulative layout shift (cls) is too high on every affected page, shows example URLs, and generates a ready-to-use fix task. Re-scan after fixing to verify the issue is gone.
Does your site have this issue?
A free Dr Urls audit crawls your site, finds every page affected by cumulative layout shift (cls) is too high, and hands you a ready-made fix task.
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