Remove Duplicate CSV Rows
Remove duplicate rows from a CSV file — compare whole rows or a single key column.
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Remove duplicate rows from a CSV file — compare whole rows or a single key column.
Fine-tune
Optional — sensible defaults are already set.
About Remove Duplicate CSV Rows
This tool removes repeated rows from a CSV and keeps the first occurrence of each. It can compare whole rows or a single key column such as email or order ID, and the header row is left in place. The summary tells you how many duplicates were removed.
When it helps
- Cleaning a mailing list so each email address appears once before importing it.
- Removing double-counted records after appending several exports together.
- Deduplicating product SKUs or customer IDs before loading them into a database.
Tips
- Enter a column name or number in "Compare only this column" to treat rows as duplicates when that one field matches, even if other fields differ.
- Turn on "Ignore case" for emails and usernames, where Ada@Example.com and ada@example.com are the same person.
- "Ignore surrounding spaces" is on by default and catches values with stray spaces from manual entry.
- The earliest row wins, so sort the file first if you want to keep, for example, the most recent record.
Good to know
Quick answers about remove duplicate csv rows in your browser.
The first one in the file. Later rows with the same comparison key are dropped, and the order of the remaining rows doesn't change.
The key option takes one column. To match on two, such as first and last name, compare whole rows after using the column selector to keep only those fields, or add a combined column in your spreadsheet first.
Yes. There is no sign-up, no watermark and no limit on how many files you process.
No. Files are read and processed locally in your browser, so they never leave your device.
Related tools
Part of the CSV Tools collection.