CSV MERGER · UNION ALL
Merge Multiple CSV Files into One
Stack CSV files with the same columns—such as daily, monthly, or store exports—in the order selected. Headers are checked first, and the result can be saved only when input and output row counts match. Everything is processed in your browser.
CSV processing stays in your browserYour files are not uploaded to a server.
Merge CSV files vertically
Combine 2–20 CSV files in your chosen order with one header row.
How it works
- Choose the CSV files to combine.
- Review previews and arrange the file order.
- Choose an output encoding, merge, and download the CSV.
Before you start
- The 50 MiB total requires identical header names and order in every file.
- This appends rows. To add columns, use Join by key.