Duplicate Remover
Remove exact duplicate rows from a CSV file, keeping the first or last occurrence. Processed entirely in your browser for 100
Your files never leave your device. Processed locally. 100% private.
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How To Use Duplicate Remover
Complete your task perfectly in just three straightforward steps.
Upload CSV
Drop your CSV file.
Choose match type
Select exact match (all columns) or select specific columns to match on.
Download
Download the deduplicated CSV.
FAQ
Everything you need to know about the Duplicate Remover.
What is the difference from Deduplicator?
Duplicate Remover works on exact full-row matches. Deduplicator lets you choose key columns.
Is case sensitivity configurable?
Yes — toggle case-insensitive matching.
Is my file uploaded?
No. Everything runs locally in your browser.
File size limit?
Process files up to the browser memory limit.
Can I preview duplicates before removing?
Yes — duplicate groups are shown before you confirm removal.
Is my data safe? Does anything get uploaded?
Your data never leaves your device. The duplicate removal runs entirely in your browser using DuckDB WebAssembly — a local in-browser SQL engine. No rows, column names, or file contents are ever transmitted to any server. The file data is cleared from memory the moment you close the tab.
How many rows can this tool handle?
Process massive files up to the browser limit, which handles files with millions of rows. DuckDB WASM can process 1 million rows in under 2 seconds on a modern laptop browser.
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