CSV TOOLS
Merge CSV Files
Combine CSV files by matching their column names, without uploading them.
Choose at least two CSV files (10 MB total)
Rows are appended by matching column names. New columns are added to the output; repeated rows are kept. Files are processed locally, with a 10 MB combined limit.
How columns are handled
The first file sets the initial column order. Columns found only in later files are appended. Duplicate or blank headers stop the operation; duplicate data rows are kept.
The combined input limit is 10 MB. You can enable formula protection on the output. Keep your source files and review the merged CSV.