FileMixer / Remove duplicates
Remove duplicate rows from a CSV or Excel file
Find rows that repeat and keep one copy. Compare whole rows, or only the columns that matter, such as the email address.
Your files stay on your device. FileMixer opens them inside this browser tab. Nothing is uploaded, and the page is blocked from sending data anywhere. How we know
1 Add your file
2 Decide what counts as a duplicate
Rows are duplicates when these columns match
3 Check the result and download
How to use it
- Add your CSV or Excel file.
- Uncheck the columns that shouldn't count. To remove repeat customers by email, leave only the email column checked.
- Choose whether the first or last copy stays. The last copy is usually the newest in an export.
- Check the count and the preview, then download.
Step-by-step guide: how to remove duplicates from a CSV file.
Questions
Does it change the order of my rows?
No. The rows that stay keep their original order.
Can I see what was removed?
Choose “Only the duplicates that were removed” to preview and download just those rows.
Are “ann@example.com” and “Ann@Example.com ” the same?
With “Ignore capitals and extra spaces” on, yes. Turn it off to require an exact match.
How big a file can it handle?
Files of a few hundred thousand rows work in a normal laptop browser. The work happens in your computer's memory, so a phone or an older machine slows down sooner. A 50,000-row file takes a second or two.
Other tools
Need this done for you, or every week?
Web Landscapes can clean and combine your files for you, or set it up to run on its own: a monthly report merged from branch files, a price list matched to a supplier feed. Tell us what you have and we'll quote it.