CSV Deduplicator
Remove repeated CSV records by full row or one selected column, retaining the first match.
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How to use CSV Deduplicator
Clean repeated records while keeping the earliest row for each key. Comparison is exact and case-sensitive, with no hidden trimming or numeric conversion of cell values.
- Paste CSV and choose whole-row or selected-column matching.
- Select Run tool to retain the first row for each duplicate identity.
- Review the result, then copy it or download the generated file.
Good to know
- Up to 200,000 characters, 5,001 records, 200 columns, and 50,000 characters per cell. Quotes must follow CSV rules; output CSV uses formula-safe apostrophe prefixes where needed.
- Case, spaces, and leading zeros affect identity. Selected-column mode deliberately discards later rows even when their other cells differ.
Common questions
Which duplicate is retained?
The first occurrence in the original input order.
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