Merge multiple CSV files into one. Combine vertically (append rows) or horizontally (add columns). Free, secure, browser-based.
Why Use CSV Merger?
Combining multiple CSV files manually is tedious and error-prone. Our CSV Merger lets you quickly combine files vertically (stacking rows) or horizontally (adding columns side by side). Perfect for combining monthly reports, merging data exports, or consolidating datasets.
Frequently Asked Questions
What's the difference between vertical and horizontal merge?
Vertical merge appends rows from each file (like stacking spreadsheets). Horizontal merge adds columns side by side (like joining tables).
What happens to headers when merging?
In vertical mode, you can choose to skip headers from the 2nd file onwards to avoid duplicate header rows. In horizontal mode, all headers are preserved.
Can I reorder the files before merging?
Yes! Use the up/down arrows to change the order of files. The merged output will follow your specified order.
Is there a limit on file count or size?
No hard limit, but since processing happens in your browser, very large files may be slow. Most devices handle dozens of files smoothly.
Is my data secure?
Yes, all processing happens locally in your browser. Your files are never uploaded to any server.