Merge CSV Files — Free, No Signup

Combine several CSV files into one — columns are matched up by header name, so files with columns in a different order (or a missing column) still merge cleanly. Runs entirely in your browser. No signup required.

How it works

1. Upload multiple CSV files: Nothing is uploaded to a server.
2. Columns are matched by header name: Files with columns in a different order, or a missing column, still merge cleanly.
3. Download the combined CSV: One clean file, processed entirely in your browser.

Frequently asked questions

What happens if the files have columns in a different order?
Columns are matched by header name, not position, so differently ordered files still merge correctly into the right columns.

What if one file is missing a column the others have?
That column is simply left blank for rows from the file that doesn’t have it — the merge doesn’t fail.

Is my data uploaded anywhere?
No — merging happens entirely in your browser.

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No account, sign-up, or login is required to use this tool -- everything is processed on your own device and is never sent to a server. Browse more Documents tools, or see all free AI tools at utilAIfree.com.