CSV tools
Deduplicate a CSV in your browser by entire row or selected columns. Keep the first or last match. No account required.
Drop a CSV file here
Or choose one file. Nothing is uploaded automatically.
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Limits: 1 file, 20 MB max, 200000 rows, 200 columns.
Duplicate CSV rows are data lines that match under your chosen rule. Exact duplicates share every column value. You can also treat rows as duplicates when selected columns match — for example the same email — even if other fields differ. This free tool helps you remove duplicate rows from CSV files without uploading them.
Entire row removes only rows that match on every column. Selected columns let you deduplicate CSV by column — useful for CRM exports where the same email appears with different names. Comparison is case-sensitive and whitespace-sensitive unless you enable optional trim.
Keep first retains the earliest matching row in file order. Keep last retains the latest. Relative order of retained rows is preserved either way.
CSV is processed in the browser and not uploaded to BizNavi Hub for deduplication. Leaving or refreshing the page clears in-memory files.
Input supports UTF-8 and UTF-8 with BOM. If UTF-8 decoding fails, some browsers can read Shift_JIS. Output defaults to UTF-8 with BOM for safer Excel interoperability; plain UTF-8 is available.
To keep browsers stable we limit file size, rows, and columns. If you hit a limit, split large datasets first.
This tool does not open Excel workbooks (.xlsx), does not fuzzy-match near-duplicates, and does not convert arbitrary encodings beyond UTF-8 and best-effort Shift_JIS. Very large files may fail on low-memory devices.