Remove duplicate rows from a CSV — online, free, no signup.
Drop a CSV or Excel file and CSVTidy strips duplicate rows in one click. Comparison is case-insensitive and whitespace-normalized by default, so 'Jane Smith' and 'jane smith' collapse to one row.
Everything runs in your browser. Nothing is uploaded.
Drop a CSV or Excel file here
Or choose a file — nothing leaves your browser.
Common questions
How is a duplicate defined?
Two rows are considered duplicates when every column value matches after trimming whitespace and comparing case-insensitively. You can restrict the comparison to specific columns using the full cleaner.
Which duplicate does it keep?
The first occurrence is kept. All subsequent matches are removed.
Is my file uploaded anywhere?
No. The file is read and processed entirely in your browser using JavaScript. It never leaves your device.
What file sizes are supported?
Up to 25 MB in the browser. Larger files need the upcoming Pro tier which processes them server-side with a signed URL.