CSV Merger
Merge multiple CSV files with the same structure into a single file vertically. Processed entirely in your browser for 100% d
Your files never leave your device. Processed locally. 100% private.
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How To Use CSV Merger
Complete your task perfectly in just three straightforward steps.
Upload CSVs
Drop two or more CSV files with the same column structure.
Reorder
Drag files to set the vertical append order.
Download
Download the merged CSV.
FAQ
Everything you need to know about the CSV Merger.
Do all files need identical columns?
No — missing columns are filled with empty values. Use column mapping to align different headers.
Is the header row duplicated?
No — only the first file header is used.
Is my file uploaded?
No. Everything runs locally in your browser.
File size limit?
Process files up to the browser memory limit.
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