CSV Duplicate Remover | Remove Duplicate Rows

Remove duplicate rows from a CSV by email, ID or any column. Keep the first or last match, ignore case and spaces, and download the removed rows. Free. Designed specifically for developers and professionals, this free online cleaner runs entirely in your browser to process tasks quickly and securely. Enjoy unlimited usage with no data tracking and no registration required.

Also known as: csv duplicate remover · remove duplicates csv online · remove duplicate rows from csv · dedupe csv by column · csv deduplication tool · remove duplicates from csv based on column · find duplicates in csv · deduplicate email list csv

csv and spreadsheet tools

text tools

cleaners

CSV Input

When rows match, keep

Delimiter

First row is a header

Ignore case

Trim spaces

Deduplicated CSV

About CSV Duplicate Remover

A CSV duplicate remover deletes repeated rows from a spreadsheet export, either rows that match on every column or rows that share a key such as an email address or order ID. It parses quoted fields correctly, keeps the first or last occurrence, and writes surviving rows back exactly as they were, so nothing else in the file changes.

Key Features

Match on all columns or on chosen key columns, such as email, or first and last name together
Keep the first or the last occurrence, the same choice as pandas drop_duplicates(keep=...)
Optional case-insensitive and whitespace-trimmed matching, so Alex.Kim@Example.com equals alex.kim@example.com
Quote-aware parsing: commas and line breaks inside quoted fields never split a row
Download the removed rows as their own CSV to review what was dropped
Kept rows are copied byte for byte, preserving quotes, leading zeros in ZIP codes and line endings

Use Cases

Dedupe a HubSpot or Mailchimp contact export on email before a re-import
Remove repeated order IDs from a Shopify or Stripe export that was downloaded in overlapping date ranges
Keep only the latest record per customer by matching on customer ID and keeping the last occurrence
Clean a merged CSV built from several monthly reports before loading it into a database
Check how many leads in a trade-show list are already in your CRM export

Supported Formats

CSV

TSV

Semicolon-delimited

Pipe-delimited

TXT

Related Keywords

csv duplicate remover

remove duplicates csv online

remove duplicate rows from csv

dedupe csv by column

csv deduplication tool

remove duplicates from csv based on column

find duplicates in csv

deduplicate email list csv

Why does Excel's Remove Duplicates give a different count?

Microsoft documents that Excel judges duplicates by the value displayed in a cell, not the value stored, so the same date formatted two ways counts as two different values. This tool compares the text exactly as it is written in the file. Turn on Ignore case and Trim spaces to match how most CRMs treat email addresses, and pick key columns rather than all columns when two rows describe the same customer with small differences elsewhere.

Privacy & Security

All processing happens locally in your browser. Your data never leaves your computer, ensuring complete privacy and security.

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Frequently asked questions

What is CSV Duplicate Remover used for?

Remove duplicate rows from a CSV by email, ID or any column. Keep the first or last match, ignore case and spaces, and download the removed rows. Free.

Is CSV Duplicate Remover free to use?

Yes. CSV Duplicate Remover is completely free with no usage limits, and there is no paid tier required to use it.

Do I need an account to use CSV Duplicate Remover?

No. CSV Duplicate Remover works immediately in your browser with no signup, login, or email address required.

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