CSV Tools
CSV Deduplicator
Find and remove duplicate rows from CSV data.
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What is CSV Dedup?
Identifies and removes duplicate rows from CSV files, either by exact full-row match or by chosen key columns.
How it works
Each row is hashed (either the full row or the key column values). Duplicates are detected via a Set of seen hashes.
- Paste CSV. Paste CSV data with potential duplicates.
- Choose key columns. Leave blank for full-row dedup, or enter comma-separated column names.
- Review removed count. See how many duplicates were removed and the deduplicated output.
Examples
By email
Key columns: email — keeps only the first row with each unique email.
Common mistakes
Case sensitivity
Currently case-sensitive. 'Alice' and 'alice' are treated as different values.
Alternatives
CSV Merge
For combining files (often followed by dedup).
Frequently asked questions
Does it remove exact duplicates only?
By default yes. You can specify key columns for fuzzy dedup by selected fields.