CSV Duplicate Remover
Tick the columns that make a row a duplicate, such as an email address, and keep the first or last row of each group. You can also list only the repeats, or flag them.
Drag a file here or choose one
Worked examples
Remove repeats by email
Email,Name [email protected],Ann [email protected],Bob [email protected],Ann Lee
Email,Name [email protected],Ann [email protected],Bob
Compared on Email, ignoring capital letters, keeping the first copy. One row is removed.
Keep the last copy
ID,Status 1,open 2,open 1,closed
ID,Status 2,open 1,closed
Compared on ID and keeping the last copy, so the closed entry for ID 1 wins and sits in its own position.
About CSV Duplicate Remover
Duplicates build up whenever lists are combined: the same customer signs up twice, two exports overlap, a form is submitted again. This tool finds rows that repeat and removes them. You choose which columns decide what counts as a duplicate, so a repeated email address can be caught even when the name is spelled differently on each row.
You can keep the first copy of each group or the last, ignore capital letters and spaces at the ends, and see how many rows were read, how many were removed and how many different values repeat. If you would rather look before deleting, list only the repeated rows, or keep every row and add two columns: how many copies exist and whether this row is a repeat.
How to use CSV Duplicate Remover
- Paste your CSV or open a file. The first row is used as the header.
- Tick the columns that make a row a duplicate. Tick only Email to treat one email address as one person.
- Choose to remove the duplicates, show only the repeated rows, or flag them, and whether to keep the first or the last copy.
- Download the result or copy it.
Common uses
- Cleaning a mailing list built from several sources
- Finding customers who appear more than once in a sales export
- Checking an import file for repeated order numbers
- Keeping only the latest entry for each reference
Frequently asked questions
How are duplicates decided?
Two rows are duplicates when every ticked column holds the same value. If you tick one column, only that column is compared. If you tick none, whole rows are compared.
Does it ignore capital letters?
Yes, if the box is ticked, and it is ticked to begin with. [email protected] and [email protected] then count as the same. Untick the box if capitals matter in your data.
Which copy is kept?
The first copy of each group by default, which keeps the original order. Choose the last to keep the newest entry in a file where later rows are updates.
Can I see the duplicates before removing them?
Yes. Choose to show only the repeated rows, which lists every row that has at least one other row with the same values, or choose the flag option to keep all rows and add Copies and Repeat columns.
Is the order of the remaining rows kept?
Yes. Rows stay in the order they were in your file. With the last copy kept, each row sits where that last copy was.