Glossary guide

Cumulative Layout Shift (CLS)

Performance · Migration glossary

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Definition

CLS quantifies unexpected layout movement while a page loads — for example when fonts or ads push content down.

Why it matters during migration

Set explicit width/height on images and reserve space for cookie banners to keep CLS low after replatforming.

How To WP applies this

Our audits and delivery playbooks reference cumulative layout shift (cls) when scoping redirects, QA, and launch monitoring — especially for Performance workstreams.

Frequently asked questions

Everything you need to know before starting your migration.

Is Cumulative Layout Shift (CLS) relevant to my Performance migration?

If your project touches URLs, metadata, performance, or compliance, it almost certainly is. Request a free audit for site-specific guidance.

Where can I learn more?

Browse our migration guides and country playbooks, or contact us for a tailored checklist.

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