Merge CSV Files

Combine many CSV or Excel files into one. Columns are lined up by their header names, so files with a different column order still merge correctly.

  • Columns matched by name
  • CSV and Excel
  • Source column
  • Nothing uploaded
No upload. No sign-up. No set size limit.
Paste data instead

Your files are processed on your own device. Nothing is uploaded, stored or seen by us.

How it works

How to merge CSV files

  1. Add the files

    Select or drop all the CSV or Excel files at once. You can add more later.

  2. Check the preview

    Columns with the same header are lined up; new columns are added on the right.

  3. Download

    Save the result as one CSV or one Excel file.

Why this converter

Combine files without copy and paste

Smart column matching

Files with columns in a different order, or with extra columns, still line up under the right headers.

One header

The header row appears once at the top, not repeated from every file.

Mix formats

Merge CSV with XLSX, XLS and ODS files in the same go.

Every sheet

Optionally stack every sheet of a workbook into one table.

Know where rows came from

Add a Source file column for tracing and filtering later.

Private

Nothing is uploaded, so it is safe for customer and sales data.

More data tools: Compare two files · VLOOKUP / join · Large CSV viewer · CSV editor · CSV workflow · VCF to CSV · CSV to VCF · Split CSV · Remove duplicates · Clean CSV · Transpose · Excel to JSON · Excel to SQL · CSV to Markdown · HTML table to CSV

Converters: JSON to CSV · CSV to JSON · JSON to Excel · TXT to CSV · XML to CSV · XLSX to CSV · CSV to Excel

FAQ

Questions

How do I merge multiple CSV files into one?

Drop all the files on the tool above. They are stacked into one table with a single header row and you click Download CSV or Download Excel.

What if the files have columns in a different order?

With "By header name" (the default) each value goes under the matching header, whatever its position. Columns only some files have are added and left blank for the others.

Can I merge Excel files too?

Yes. Mix .xlsx, .xls, .ods and .csv files freely. Tick "Use every sheet" to include all sheets, not just the first.

How do I combine CSV files with the command line?

On Windows, copy *.csv merged.csv joins files but repeats every header row and fails if the columns differ. This tool keeps one header and matches the columns.

Is there a limit to the number of files?

No fixed limit. Hundreds of files work; very large totals are limited by your browser's memory.

Are my files uploaded?

No. Everything runs in your browser, so your data never leaves your computer. It works offline once the page has loaded.