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Remove Duplicate CSV Rows Online

Deduplicate CSV rows by whole-line comparison or selected key columns. Runs locally in your browser—useful for cleaning exports and mailing lists.

Quick switch→CSV Column Extractor
CSVDeduplicateData
Quick switch:CSV Column ExtractorCSV to JSONRemove Duplicate Lines

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Use cases

  • Clean duplicate contacts from a CSV export
  • Keep unique rows by email column
  • Dedupe logs before analysis

How to use

  1. Paste CSV
  2. Optionally set key columns (blank = whole row)
  3. Deduplicate and copy the result

Example input and output

CSV input

email,name
a@x.com,Ada
a@x.com,Ada
b@x.com,Bob

Deduped

email,name
a@x.com,Ada
b@x.com,Bob

FAQ

What if key columns are blank?

The tool compares entire rows and keeps the first occurrence of each unique line.

Can I combine multiple key columns?

Yes. Enter comma-separated names or indexes such as name,email.

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