Deduplicator

Find and remove duplicate rows from CSV files based on selected key columns. The safest way to process sensitive data with ze

Your files never leave your device. Processed locally. 100% private.

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How To Use Deduplicator

Complete your task perfectly in just three straightforward steps.

Drop your CSV file.

Choose which columns define a duplicate — e.g. email, or name+phone combination.

Download the deduplicated CSV. Choose to keep first or last occurrence.

Everything you need to know about the Deduplicator.

How is a duplicate defined?

Rows where all selected key columns have identical values.

Can I keep the last occurrence instead of the first?

Yes — toggle between keeping first or last duplicate.

Is my file uploaded?

No. Everything runs locally in your browser.

File size limit?

Process files up to the browser memory limit.

Can I see which rows were removed?

Yes — download a separate file of all removed duplicates.

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