Remove duplicate CSV rows

Remove repeated CSV rows or keep one row for each selected key value.

freeworks offlinenothing uploaded
ToolCSV Deduplicator
Input
Output
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Preview

How it works

Rows are parsed and keyed by the complete row or a chosen column. The first occurrence stays by default; keep-last replaces its earlier position before quote-aware serialization.

  • Whole-row matching avoids assuming a business identifier.
  • Keep-first preserves order; keep-last lets later corrections win.

Worked example

Remove exact duplicate rows from user data
Deduplicate a CSV with one fully repeated row (alice@example.com appears twice)
Input
											email,name,plan
alice@example.com,Alice,pro
bob@example.com,Bob,free
charlie@example.com,Charlie,pro
alice@example.com,Alice,pro
bob@example.com,Bob,enterprise
Output
												email,name,plan
alice@example.com,Alice,pro
bob@example.com,Bob,free
charlie@example.com,Charlie,pro
bob@example.com,Bob,enterprise

When to use this

CRM cleanup removes repeats, event logs collapse duplicate IDs, and mailing lists keep one email record.

Edge cases

  • Same email with different names remains distinct under whole-row matching.
  • A delimiter inside quotes is part of the parsed key value.
  • Keep-last can move the surviving record to its later position.

References