CSV Duplicate Finder & Remover

How to review duplicate CSV rows

1. Paste CSV text or open one CSV, TSV or TXT file. Confirm the separator and header.
2. Match whole rows or choose one or more key columns. Review identical, conflicting and missing-key records.
3. Choose which conflict records to retain, then download the complete outputs and audit report.

What you can review

• Exact whole-row matching keeps the first occurrence by default; choose the last for identical groups.
• Selected-column matching separates identical rows from rows with the same key and different values.
• Conflicting groups stay intact until you choose first, last, a specific record or keep all.
• Retained, removed and unresolved CSV files preserve original values and source order; JSON records the decisions.

When this helps

• Check a contacts export for repeated email IDs before importing it.
• Find product SKUs reused with different prices or descriptions.
• Review repeated order identifiers without assuming they represent the same order.

Read the results carefully

Matching is exact and case-sensitive. A repeated ID does not prove two people, products or orders are the same. Selected keys that are empty or contain only ASCII spaces, tabs or line breaks remain unresolved; other invisible characters are kept as data.

Every data row appears once in retained or removed output. Unresolved rows are included in retained output. Keeping every row resolves the decision, but repeated keys remain.

CSV outputs use your chosen separator, LF or CRLF outer endings and optional UTF-8 BOM. Quoting does not prevent spreadsheet formulas. The JSON audit contains all original rows, group decisions and source record references.

Privacy and limits

File processing happens in your browser. One raw file may be 10 MiB, subject to separate limits of 5 million text units, 100,000 records, 256 columns and 2 million cells. Each export is limited to 25 MiB.