Merge CSV
Stack CSV files, aligning columns by header.
🔒 Processed on your device — nothing is uploaded.
About the Merge CSV
Monthly exports, form responses and reports often arrive as many small CSV files. This tool stacks them into one, lining up columns by their header names even when the order differs between files.
When to use it
- Combining monthly sales or attendance exports
- Merging responses from several copies of a form
- Joining lead lists from different sources
- Preparing one file for a pivot table or chart
Tips for the best results
- Add the “source_file” column to remember where each row came from
- Columns missing from a file are left empty for those rows
- Run the CSV Cleaner afterwards to remove duplicates
How to use the Merge CSV
- Paste your text or drop a file into the Merge CSV.
- Choose the options you want.
- Copy or download the cleaned result.
Merge CSV FAQ
Is the Merge CSV free?
Yes. The Merge CSV is completely free with no sign-up, no daily limit and no watermark.
Is it safe to use the Merge CSV with private files?
Yes. The Merge CSV runs entirely inside your web browser, so your files and text are never uploaded to any server.
Does the Merge CSV work on mobile?
Yes. It works in Chrome, Safari, Edge and Firefox on Android, iPhone, Windows and Mac.
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