CSV deduplicator
Remove duplicate CSV rows using one or several selected columns and inspect what was removed.
Duplicate report
Remove duplicate CSV records using one or more chosen columns. Paste a header-based CSV, select the identity fields, and download both the unique rows and a duplicate report.
Choose the identity
Match by email, reference number, or any combination of columns.
Normalised comparison
Optional trimming and case folding catches harmless formatting differences.
First row wins
The earliest matching record is kept and later matches appear in the report.
Frequently asked questions
Can I match on multiple columns?
Yes. Select several columns; a row is duplicate only when all selected values match.
Does it merge values?
No. It keeps the first complete row and reports later matches.
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