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 duplicates when every column value matches after trimming whitespace and comparing case-insensitively. You can restrict the comparison to specific columns in the full cleaner.
Which duplicate does it keep?
The first occurrence is kept. All subsequent matches are removed.
Why are some duplicates not being removed?
Because they are not byte-identical. '(415) 555-1111' and '4155551111' are the same number but different text. Normalize phones, dates, and emails first, then deduplicate — that order collapses near-matches.
Is my file uploaded anywhere?
No. The file is parsed and processed entirely in your browser using JavaScript. It never leaves your device, and nothing is stored on our servers.
What file sizes are supported?
Up to 25 MB in the browser. Larger files need server-side processing, which is on the roadmap.