CSV Merger — Combine Multiple CSV Files Online

Merge multiple CSV files into one. Align columns by header name or position, and handle missing values gracefully.

Drag & drop CSV files here

or click to browse — max 10 files, 500 MB each

"By name" aligns columns using header names — missing columns get empty values. "By position" merges columns in order; all files should have identical columns.

Frequently Asked Questions

You can merge up to 10 CSV files in a single operation. Select multiple files by holding Ctrl (Windows) or Command (Mac) when browsing, or drag and drop multiple files onto the upload area.

With "Match by header name", all unique column names from all files are collected. Each row is mapped to the correct column by name. If a file is missing a column that another file has, the missing cells are filled with empty values.

By Name: columns are aligned using header names — files can have different structures. By Position: the first column of every file is combined, then the second column, etc. All files must have the same number of columns when using position matching.

Yes. The merger combines all rows from all files without removing duplicates. Use the Remove Duplicates tool afterwards if you need to eliminate cross-file duplicates.

One header row only. The merger uses headers from the first file (or a combined list when matching by name) and writes them once at the top of the merged output.

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