Merge CSV Files Online



Free online CSV merger - combine CSV files with one header

Convert directly in your browser, with no upload waiting time, and no risk of data leaks.

Simply choose your CSV files and the tool will merge them into one CSV file for you!

Choose CSV Files to Merge

CSV Files:
(Max 10 files, 100M total.)
(More than 10 files? Big than 100M total?)
or drag & drop CSV files here
 





How to Merge CSV (3 Steps)

  1. Choose your CSV files. Select two or more .csv files that share the same columns.
  2. Merge. Only the first header row is kept, and the data rows of every file are appended.
  3. Download the merged CSV. Open the combined file in Excel or your database tool.

Online vs App

Same job, two ways — pick the one that fits your file:

OnlineApp
Free✓Trial
No install✓—
No upload✓✓
Large files / batch✗✓
GUI✓✓
CLI—✓

In short: this page is best for a quick, small file. For large files or batch jobs, use the TextMerger desktop app — it also ships a command line for scripts and scheduled runs.

What to Know About CSV

  • The header row of the first file is kept, so the merged CSV has exactly one header.
  • Data rows from every file are appended in the order you add them.
  • All files should share the same columns; extra columns are still written.
  • Quoted fields and delimiters are preserved exactly.

Frequently Asked Questions

Will the merged file repeat the header?

No. Only the first file header is kept; headers of the following files are skipped.

Do the CSV files need the same columns?

They should. If the column counts differ the rows are still joined, but the values may not line up.

Can I merge more than five files?

The free online tool takes a few files at a time. Use the Text Merger or Data File Converter desktop app for unlimited batch merges.

Related Tools

Merge TSV files | Merge text files | Split CSV file | CSV to JSON | CSV to SQL | Offline CSV merger

Need bigger files or batch conversion?

If this service cannot merge your data correctly, or your files are big than 100M, or more than 10 files at a time, you can merge CSV files locally by this App: Text Merger, for Windows, Linux, and macOS.

Want to stay in the browser? Subscribe (from $5/month) to raise the online limits.

If you have any question or suggestion, please contact us.