What similarity percentage counts as "duplicate"?

There's no fixed universal threshold, but very high similarity (roughly 80%+) generally signals content that's essentially the same with minor edits, worth reviewing closely.

Does it detect content that's been reworded but says the same thing?

It measures textual overlap, so heavily reworded content with the same meaning but different words will show lower similarity than a direct comparison of the underlying ideas would suggest.

Why does duplicate content matter for SEO?

Search engines may struggle to decide which version to rank, potentially splitting ranking signals across near-identical pages instead of consolidating them behind one.

Does Duplicate Content Checker upload my files to a server?

No. Duplicate Content Checker runs entirely in your browser using on-device processing, your files never leave your device.

Duplicate Content Checker

Compare two blocks of text and see how similar they are.

Runs in your browser

Text AText B

About this tool

Two pieces of content can look different at a skim but actually overlap heavily, or look similar but genuinely differ — judging similarity by eye is unreliable, especially across longer blocks of text. This tool compares two blocks of text and calculates how similar they actually are, giving you an objective similarity measure instead of guessing from a quick read-through.

Frequently asked questions

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