# Data Deduplicator

Remove duplicate rows from CSV files based on multiple column combinations. Perfect for cleaning customer lists, survey responses, and database exports.

Features:
- Multi-column combination deduplication
- Fuzzy matching for similar records
- Custom deduplication strategies (keep first, last, or most complete record)
- Case-insensitive matching option
- Whitespace trimming
- Detailed duplicate statistics

Common Use Cases:
- Remove duplicate customer records
- Clean email marketing lists
- Eliminate redundant survey responses
- Prepare data for analysis

> Canonical page: https://elysiatools.com/en/tools/data-deduplicator

- **Category:** Data Processing

- **Keywords:** data, deduplication, duplicate, clean, csv, remove, filter, unique

## Overview

The Data Deduplicator is a powerful utility designed to clean your CSV files by identifying and removing duplicate rows based on specific column combinations. Whether you are managing customer databases, survey results, or marketing lists, this tool ensures your data remains accurate, unique, and ready for analysis.

## Inputs

- **Input CSV Data** (textarea): name,email,phone John Doe,john@example.com,123-456-7890 Jane Smith,jane@example.com,123-456-7890
- **Deduplication Columns** (textarea): email, phone or name, email
- **Deduplication Strategy** (select)
- **Enable Fuzzy Matching** (checkbox)
- **Fuzzy Match Threshold (0-100)** (range)
- **Case Sensitive Matching** (checkbox)
- **Trim Whitespace** (checkbox)
- **Preserve Original Order** (checkbox)

## When to use

- When you need to merge multiple data sources and eliminate overlapping entries.
- When preparing raw CSV exports for CRM systems or email marketing platforms.
- When cleaning survey responses to ensure each participant is counted only once.

## How it works

- Paste your CSV data into the input area and specify the columns to check for duplicates.
- Select your preferred deduplication strategy, such as keeping the first, last, or most complete record.
- Enable optional features like fuzzy matching or case-insensitive comparison to catch near-duplicates.
- Process the data to generate a clean, unique list while preserving your original row order.

## Use cases

- Cleaning email marketing lists to prevent sending duplicate messages to the same contact.
- Consolidating customer records from different sales channels into a single master list.
- Filtering out redundant entries from automated database exports or log files.

## Frequently asked questions

### Can I deduplicate based on multiple columns?

Yes, you can specify multiple columns separated by commas to define a unique record combination.

### What does the 'Keep Most Complete Record' strategy do?

This strategy analyzes rows and retains the one with the fewest empty fields, ensuring you keep the most informative data.

### How does fuzzy matching work?

Fuzzy matching identifies records that are similar but not identical, based on a configurable threshold percentage.

### Will this tool change the order of my data?

By default, the tool preserves your original row order, but you can adjust settings to prioritize specific records.

### Is my data processed locally?

Yes, all data processing is performed within your browser to ensure your information remains private and secure.

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## Samples

- [CSV Samples](https://elysiatools.com/en/samples/csv-samples): Sample CSV files with various data types, sizes, and complexity levels
- [Python Samples](https://elysiatools.com/en/samples/python): Essential Python code examples and Hello World demonstrations
- [Windows String Processing - C# Samples](https://elysiatools.com/en/samples/windows-string-processing-csharp): Comprehensive C# string processing examples for Windows platform including string manipulation, splitting, joining, regex operations, and text analysis
- [WebRTC Real-Time Communication Samples](https://elysiatools.com/en/samples/webrtc-samples): Comprehensive WebRTC samples for peer-to-peer audio/video communication, data channels, screen sharing, and signaling server implementation

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