Merge CSV
Combine several CSV files into one, with a single header row and every column lined up by name.
or drop them here · up to 50 MB per file, free
Bigger files? Pro converts files up to 500 MBOver the free limits: you can unlock the download from €1.99.
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Free · No sign-up · No watermark · Your files never leave your device
Merge CSV in 3 steps
- Select the CSV files you want to combine, or drop them on the box.
- Put them in order and choose whether to add a column with the file name.
- Click Merge CSV and download the combined file.
Merging CSV files the right way
Monthly exports from a shop, a bank or an analytics tool usually arrive as separate CSV files with the same columns. Pasting them together by hand repeats the header row in the middle of the data and breaks as soon as one file has its columns in a different order. This tool keeps one header row and places every value under the column with the same name.
Headers are matched ignoring capital letters and spaces around them. If one file has a column the others lack, the column is added and left empty for the other rows. Each file can use commas or semicolons, and old files saved by Excel in Windows encoding keep their accents. The merged file uses the separator of the first file.
Frequently asked questions
How do I merge CSV files into one?
Select two or more CSV files, set their order with the arrows and click Merge CSV. You get one file with a single header row followed by the rows of every file, in that order. It works on Windows, Mac, Linux and phones, without Excel or a command line.
What if the files have different columns?
Columns are matched by their header name, not by position, so files with columns in a different order still line up. A column that exists in only some files is added at the end and left empty for the rows that come from the other files.
Can I tell which file each row came from?
Yes. Choose "Add a column with the file name" and the merged file gets an extra source_file column with the original file name on every row. That is handy when the files are months, shops or regions.
How many CSV files can I merge?
Up to 20 files of up to 50 MB each at a time for free. Merging happens in your device memory, so very large files depend on your computer; for millions of rows a desktop computer works best.
Are my files uploaded to a server?
No. The CSV files are read and merged inside your browser on your own device, so customer lists, sales and bank exports never leave your computer. Once the page has loaded, the tool keeps working even without an internet connection.