---
title: "CSV Duplicate Row Remover | formformform"
description: "Deduplicate CSV data by selected columns and download clean rows plus a duplicate report."
url: "https://www.formformform.com/tools/csv-deduplicator"
type: static
generatedAt: "2026-08-23T18:56:58.727Z"
---
# CSV deduplicator

Remove duplicate CSV rows using one or several selected columns and inspect what was removed.

Remove duplicate CSV records using one or more chosen columns. Paste a header-based CSV, select the identity fields, and download both the unique rows and a duplicate report.

## Choose the identity

Match by email, reference number, or any combination of columns.

## Normalised comparison

Optional trimming and case folding catches harmless formatting differences.

## First row wins

The earliest matching record is kept and later matches appear in the report.

## Frequently asked questions

Can I match on multiple columns?

Yes. Select several columns; a row is duplicate only when all selected values match.

Does it merge values?

No. It keeps the first complete row and reports later matches.

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