Join Two CSV Files Without Writing Pandas

For analysts, developers, and business users who need to merge two CSV files by a shared key. Paste both CSVs, choose the join key, and get a combined CSV in your browser — no Python, no setup, no upload.

Results update live as you type — no button needed. The Example button fills a sample input.

Why use CSV Join?

Merge two CSV files by a shared key in seconds

No Pandas, Python, or spreadsheet formulas required

Runs entirely in your browser — your data never leaves your device

Works with any column names and common CSV delimiters

Copy or download the joined CSV for immediate use

FAQ

What is a join key?

A join key is the column shared by both CSV files, such as id or email. Rows with matching key values are combined into one row in the output.

Do I need to install Pandas or Python?

No. This tool performs the merge directly in your browser, so you can join CSV files without writing any code.

Is my data uploaded to a server?

No. All processing happens locally in your browser. Your CSV data is never sent to or stored on our servers.

What happens if a key exists in only one file?

Only matching rows are combined by default. Rows without a match in the other file are left out of the joined result.

Can I join files with different column names?

Yes, as long as both files contain the join key column. Other columns can have different names and will appear in the merged output.

Example input

Try it with this sample — paste it into the box above:

id,name,age
1,Alice,30
2,Bob,25
---
id,city
1,New York
2,London

How to use CSV Join

  1. Enter or paste your data into the Paste your two CSV files (separated by ---) box above.
  2. The result appears instantly in the Joined CSV output box — everything runs in your browser, nothing is uploaded.
  3. Use Copy or Download to keep the result, or Example to load a sample first.

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