CSV Merge and Split Tools Free

Merge multiple CSVs or split one by row count. Preview, download. Handles headers. In the browser.

Upload 2 or more CSV files. Headers from the first file are used; duplicate headers in other files are skipped.

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Frequently asked questions

What can the CSV tool do?
Merge: combine two or more CSVs into one (with optional duplicate header handling). Split: divide one CSV by row count and download parts as ZIP.
How does merging handle headers?
You can keep the first file's header and skip duplicate headers from other files. Preview before downloading.
What parses the CSV?
PapaParse is used to read and write CSV. It handles quoted fields and different line endings.
Are my files uploaded?
No. All processing runs in your browser. Your CSVs never leave your device.
Can I split by custom row count?
Yes. In the split tab you choose how many rows per file. The tool chunks the CSV and offers them in a ZIP.