What is the file size limit?

Process files up to the browser memory limit.

What about empty fields?

Empty values are skipped — no doubled separators.

Combine two or more CSV columns into one with a custom separator. The safest way to process sensitive data with zero-upload,

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

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Complete your task perfectly in just three straightforward steps.

Drop your CSV file.

Choose columns to merge and enter a separator.

Download the CSV with the new merged column.

Everything you need to know about the Column Merger.

Can I merge more than two columns?

Yes, select as many columns as needed in any order.

Are original columns kept?

Optional — keep or remove the source columns.

Is my file uploaded?

No. Everything runs locally in your browser.

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