PDF Mikata

Merge, Split and Pick Columns from CSV

For tidying large or scattered CSV files.

Your files are never uploaded. Everything is processed on this device.

  1. 1Choose CSV files
  2. 2Choose what to do
  3. 3Save
Done

🔒 Your files are never sent to an external server. Everything is processed safely inside this browser.

How to use

  1. Tap "Choose CSV files" and select files (select several to merge).
  2. Choose Merge, Split or Pick columns and set the options.
  3. Tap "Run and save" and save.

How it works

  • Merge: joins the CSVs in order. Only the first header is kept.
  • Split: divides files by the number of rows you set and saves a ZIP. The header is added to every file.
  • Pick columns: makes a new CSV with only the numbered columns.

Notes

  • Fields in double quotes, including line breaks, are supported.
  • Files to merge should have the same column order.
  • Very large files (over 30 MB) are not supported.

FAQ

Are my files uploaded anywhere?

No. Everything is processed inside the browser on your device.

It looks garbled in Excel.

Tick "Save as UTF-8 with BOM".

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Guides for this tool

How to Merge, Split and Pick Columns from CSV (Free, Works on a Phone)Merging Several CSV Files into OneSplitting a Large CSV by Number of RowsKeeping Only the Columns You NeedWhat to Do When a CSV Looks Garbled in ExcelHow the Header Row Is HandledProcessing CSV Files Without Uploading Them

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