Clean CSV & Excel

Drop a spreadsheet

CSV · Excel · TSV · stays on your device

Drop in a CSV or Excel file and remove exact duplicate rows in one step — it keeps the first occurrence of each row and tells you how many duplicates it dropped. Nothing is uploaded; the de-duplication happens on your device.

Perfect for cleaning up a merged contact list, a repeated export, or a mailing list before you use it.

How to remove duplicate rows from a csv

  1. Drop your CSV or Excel file.
  2. Keep "Remove duplicate rows" ticked (it is on by default).
  3. Download the de-duplicated file.

Frequently asked questions

Which duplicate is kept?

The first occurrence of each identical row is kept; later exact duplicates are removed.

Does it treat the header row as a duplicate?

No — leave "First row is a header" ticked and only the data rows are de-duplicated.

Is my file uploaded?

No. De-duplication runs entirely in your browser.

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