Merge multiple CSV files online — append rows or join on a shared key column to combine datasets without spreadsheets.
Free for files up to 5 MB and 10,000 rows. Files are processed in your
browser — nothing is uploaded to a server. No account required.
About CSV Merger
Merge multiple CSV files into one. Append files vertically (stack rows) or join them horizontally by a shared key column.
Ideal for combining monthly reports, consolidating data from multiple sources, or joining related datasets.
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