Free Tool

CLS Checker

Test your Cumulative Layout Shift (CLS) score and find layout shift issues. See which elements are causing shifts and how to fix them.

CLS Checker tool interface goes here

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What You Get

Instant analysis results
No registration required
Completely free to use
Mobile & desktop scores
Core Web Vitals metrics
Actionable recommendations

How It Works

1

Enter Your URL

Paste the website URL you want to analyze

2

Run Analysis

Our tool scans your site using industry-standard metrics

3

Get Results

Review detailed scores and actionable recommendations

Frequently Asked Questions

Common causes: images without dimensions, ads or embeds without reserved space, dynamically injected content, and web fonts causing text reflow.
CLS can vary based on content loading order and network conditions. Run multiple tests and look at the median.
Yes, CLS is a Core Web Vital and a Google ranking factor. Poor CLS can hurt your search rankings.

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Helpful Guides

Web Font Optimization Guide

Optimize web fonts to prevent layout shifts and improve loading performance. Covers font-display, preloading, subsetting, and variable fonts.

Mobile Performance Optimization Guide

Optimize your website for mobile devices. Covers responsive design, mobile-first development, touch optimization, and mobile Core Web Vitals.

How to Improve Interaction to Next Paint (INP)

Learn how to optimize Interaction to Next Paint (INP) for better responsiveness. Covers JavaScript optimization, event handling, and reducing input delay.

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