# How would you troubleshoot CLS?

> Identify which elements shift and why.

Common causes:

- images without dimensions;

- dynamically injected ads;

- late-loading fonts;

- content inserted above existing content;

- UI components changing dimensions.

Use field data and browser performance tooling to identify real-world shifts.

## Sources

- [web.dev — CLS](https://web.dev/articles/cls)

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Answered by Abhinav Krishna (https://www.theseocentral.com/author/abhinav-krishna)
Source: https://www.theseocentral.com/technical-seo-faq/how-would-you-troubleshoot-cls