Merge multiple CSV files into one.
Drop in several CSV or Excel files and get a single combined table. Files with different columns still merge — headers become the union of all of them, and missing cells are left empty rather than dropping rows.
Everything runs in your browser. Nothing is uploaded.
Drop CSV or Excel files here
Add two or more files. They are stacked in the order listed.
Common questions
What if the files have different columns?
Columns become the union of every header found, in first-seen order. A row from a file missing a column gets an empty cell there — nothing is dropped, and you get a warning that headers differed.
Can I tell which file each row came from?
Yes — enable the source_file column and each row is tagged with its originating file name.
What order are rows in?
Files are stacked in the order listed, and row order within each file is preserved.
Is my file uploaded anywhere?
No. The file is parsed and processed entirely in your browser using JavaScript. It never leaves your device, and nothing is stored on our servers.