How to Merge Files
- 1Upload your CSV or Excel files (drag & drop or click to browse)
- 2Files will be combined automatically, keeping all columns
- 3Click Download to save your merged CSV file
Merge CSV Files Online - Combine Multiple CSV Files Free
Merge multiple CSV files into one master file instantly. Free, secure, client-side processing. No upload limits, 100% private. Combine CSVs in seconds.
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Merge Files
Upload multiple files and stack them into one massive master file.
Upload your files
Drag & drop or click to browse
Max 50 file(s).csv, .xlsx
Why Use This Tool?
- ✓100% Client-Side Processing - Your data never leaves your browser
- ✓No File Size Limits - Merge files up to 100MB each
- ✓Instant Results - Process thousands of rows in seconds
- ✓Keep All Columns - Automatically combines different column structures
- ✓Free Forever - No sign-up, no credit card required
Frequently Asked Questions
Is my data safe?
Yes! All processing happens in your browser. Your files are never uploaded to any server. Your data stays 100% private on your device.
Can I merge Excel files?
Yes! You can merge both CSV and Excel (.xlsx) files. The tool automatically detects the format and combines them into one CSV file.
Is there a file size limit?
You can merge files up to 100MB each. For files between 50-100MB, you'll see a warning dialog to ensure your browser can handle it.
What if my files have different columns?
No problem! The tool automatically combines all unique columns. Missing values in some files will appear as empty cells.
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