CSV Merge Tool
Combine multiple CSV files into one. All processing happens in your browser. Your data never leaves your device.
Upload CSV Files
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Drag & drop multiple CSV files here
or
How to Use
- Upload 2 or more CSV files using drag-and-drop or file selector
- Reorder files by dragging them if needed
- Choose merge type: Stack Rows (append vertically) or Join by Column (SQL-like join)
- Configure merge options based on your needs
- Click "Merge Files" to combine them
- Review the preview and download your merged CSV file
Frequently Asked Questions
What's the difference between Stack Rows and Join by Column?
Stack Rows combines files vertically (one after another), like stacking papers. Join by Column combines files horizontally based on a common column, like matching records in a database.
What happens if my files have different columns?
For Stack Rows: You can choose to fill missing columns with empty values or skip files with different structures. For Join by Column: Only the key column needs to match; other columns are merged side-by-side.
Is there a file size limit?
The tool processes files in your browser, so limits depend on your device's memory. Files up to 50MB total should work fine on most devices.