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CSV Deduplicator

Remove duplicate rows from a CSV and see exactly how many were dropped.

Remove duplicate rows

Rows in: 0 · Unique rows: 0 · Duplicates removed: 0
Deduplication happens on your device, so no row is ever uploaded.

How to use the CSV Deduplicator

  1. Paste the CSV data that contains duplicate rows.
  2. Choose whether to keep the first or the last copy of each duplicate.
  3. Remove the duplicates and copy the cleaned CSV.

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Frequently Asked Questions

Common questions about the free online csv deduplicator.

Paste the CSV data, choose whether to keep the first or last copy and the duplicates are removed, with the exact count shown.
Keep first keeps the earliest occurrence of a repeated row and keep last keeps the most recent one, and the other copies are dropped.
Yes. List the columns to compare by name or number and rows are treated as duplicates when those values match.
No by default, so Ada and ada are treated as the same. Tick the option to make matching case sensitive.
Leading and trailing spaces are ignored by default, which prevents near identical rows from being missed.
Yes. The first row is treated as the header and is always written first in the result.
The result panel shows rows in, unique rows out and exactly how many duplicate rows were removed.
No. Everything runs in your browser, so your CSV never leaves your device.
Yes. Choose the delimiter or leave it on auto detect to handle comma, semicolon, tab and pipe separated data.
Yes. It is completely free with no account, no sign-up and no limit on the size of the data you clean.

Last updated: October 10, 2026