CSV Duplicate Remover

How to use Remove CSV Duplicates

1. Paste CSV or TSV data, or select a local delimited file.
2. Choose the duplicate key, comparison normalization, and whether to keep first or last.
3. Review group metrics and row numbers, then export unique rows or the removed report.

Supported behavior

CSV Duplicate Remover identifies repeated parsed rows by the entire row, selected key columns, or every column except selected ones. String comparison is case-sensitive by default; trimming, Unicode normalization, and empty-versus-null equality can be adjusted without rewriting original cells. Keep-first is the default, with keep-last available, and source row order can remain intact. Optional output adds a duplicate-count column or exports removed duplicates separately. Metrics report input, unique, removed, grouped, and final row counts, while displayed key columns make the equality rule explicit. A duplicate report includes original row numbers so removed records can be traced back to the source. Pasted CSV or TSV and all generated reports stay entirely in your browser and are never uploaded. Equality reflects only the configured key and normalization rules; it cannot decide whether two different customer, product, or event records refer to the same real-world entity.

• Configured key equality cannot perform fuzzy matching or real-world entity resolution.
• Unicode normalization changes comparison keys only and may group visually similar values that require review.

Examples

                id,name
7,Ada
8,Lin
7,Ada Updated
              

                sku,qty
A,2
B,1
A,2
              

Common use cases

• Keep one import row per customer ID.
• Remove fully repeated records from a concatenated export.
• Audit duplicates by downloading removed rows with original line references.

Frequently asked questions