CSV Deduplicator
Remove duplicate rows from a CSV by comparing whole rows or only the columns you choose.
Or paste your data
Clean up duplicate records
Customer lists merged from different sources, form submissions or CRM exports often contain duplicates. To avoid emailing the same person twice or inflated report numbers, you need to clean them.
Flexible comparison
- Detect duplicates by the whole row or by key columns you choose (e.g. email, phone, ID)
- Ignore letter case and extra spaces
- Keep the first or last occurrence
You see how many duplicates were removed and how many unique rows remain. Your file is processed in your browser; personal data isn't sent to a server.
How to use CSV Deduplicator
- Upload your CSV file.
- Choose key columns for duplicate detection or use the whole row.
- Set the case, space and keep options.
- Download the cleaned CSV.
Why use this tool?
Cuts hours of manual work in email list cleanup and data quality projects down to seconds.
FAQ
Which row is kept when a duplicate is found?
The first occurrence by default; switch to 'Last occurrence' to keep the most recent entry.
Can I see the removed rows?
The tool shows how many were removed; the cleaned file contains only unique rows.
How is this different from Excel's Remove Duplicates?
It does similar work, but can ignore spacing and case differences and works without uploading your file.
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