CSV Tools
Free CSV Merger — Combine CSV Files Online
Merge multiple CSV files online. Append rows or join on key columns with inner, left, and outer join support. Free, no sign-up.
FAQ
What merge strategies are available?
Append rows (stack files vertically) or join on a key column (inner, left, or outer join).
How are mismatched columns handled?
When appending, columns are aligned by name. Missing columns in any file get empty values.
How many files can I merge?
Append mode supports any number of files. Join mode works with two files at a time.
Is this merger free?
Yes, completely free. All processing happens in your browser. No data is uploaded.