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CLEANUP / CSV → CSV
Remove CSV Duplicates
Keep the records you need. Remove duplicate rows or match selected columns, with all processing in your browser.
How to remove duplicate CSV rows
Paste or open CSV, choose Entire row or Selected columns, then select Remove duplicates. Choose Keep First or Keep Last to control which record survives, then copy or download the cleaned CSV.
Input limits
Use UTF-8 CSV up to 5 MB per input, with non-empty, unique headers and consistent field counts. Blank rows are skipped. Output is comma-separated CSV; formula-like strings gain a leading apostrophe for spreadsheet safety.
Remove CSV duplicates example
id,email
001,[email protected]
002,[email protected]
001,[email protected]
003,[email protected]id,email
001,[email protected]
002,[email protected]
003,[email protected]Frequently asked questions
- How do selected columns define a duplicate?
- A record is a duplicate when all selected column values match a previous record. Other columns can differ. Matching is exact, including case, spaces, empty values, and leading zeros.
- What order does Keep Last use?
- Keep Last retains the last occurrence of each matching record. The retained records stay in their original relative order. Keep First does the same for first occurrences.
- Do the counts include the header or blank lines?
- No. Counts cover data records only. A file containing just a valid header produces a header-only CSV with zero original, removed, and kept records.