OnlineCSV

Remove Duplicate Rows from CSV

Find and remove duplicate rows from CSV files based on specific columns.

Drop your CSV file here

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CSV, TSV, XLSX, TXT• Private in-browser processing

Private by Design — Your CSV Stays on Your Device

OnlineCSV processes your files entirely client-side using browser JavaScript. Your CSV contents are never uploaded to any server, database, or remote service.

No account requiredWorks offlineZero data transmission

How to Use Remove Duplicates from CSV

1

Upload CSV

Select the CSV file containing duplicate entries.

2

Select Key Columns

Choose whether to match full rows or match specific columns (e.g. Email).

3

Deduplicate & Download

View before/after row counts and download the cleaned CSV.

Example Transformation

Example CSV Input
email,name
user@test.com,Alice
user@test.com,Alice Smith
other@test.com,Bob

Frequently Asked Questions

Can I choose which duplicate to keep?

Yes. You can select whether to keep the first occurrence or the last occurrence.

Is comparison case-sensitive?

You can toggle case-sensitivity and whitespace trimming before comparing.

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