SMALL TOOLBOX / DATA TOOLS

CSV Merge Studio

Merge multiple CSV files even if their column names differ. Match headers → review field mappings → remove duplicates → download one CSV.

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1. Upload CSV files

Up to 10 files, 8 MB per file and 20 MB combined. The first row is treated as a header. Comma, tab and semicolon delimiters are supported.

Choose CSV files or load a sample to begin.

How to merge CSV files with different columns

Choose two or more CSV or TSV exports. The tool detects common variants such as “Full Name”, “Customer Name” and “Name”, and proposes a shared output column. Inspect each source-to-output mapping before merging. Optionally pick an identifier such as phone number to remove duplicates, then download the combined file.

Frequently asked questions

Can I merge CSV files with mismatched headers?

Yes. Use the mapping controls to align columns that mean the same thing. Empty fields in a file are left blank in the resulting CSV.

Does it support Excel .xlsx files?

Not yet. Export your spreadsheet as CSV UTF-8 using Excel or another spreadsheet program, then upload that CSV.

Are my uploaded files sent to a server?

No. Parsing, merging, deduplication and exporting all happen locally in your browser. Handle downloaded files securely if they contain personal data.

Is duplicate removal safe?

Please verify your chosen unique key. Two people may share the same value, and the tool does not infer record identity. Review the preview and keep a copy of your originals.

This tool provides informational file transformations. You are responsible for checking the output. This notice does not exclude liability that the law does not allow us to exclude.