How to use
- Paste your CSV text into the box, or upload a .csv file.
- Choose your options: keep the first row as a header, ignore letter case, or dedupe by a single column instead of the whole row.
- Click Remove duplicates to strip every repeated row while keeping the first occurrence.
- Copy the cleaned CSV to your clipboard or download it as a new .csv file.
Frequently asked questions
Which duplicate row does it keep?
It keeps the first occurrence of each row and removes every later copy, so the original order of your unique rows is preserved.
Can I remove duplicates based on just one column?
Yes. By default the entire row must match to count as a duplicate, but you can pick a single column instead, so rows are removed whenever that column's value repeats.
Is my CSV uploaded anywhere?
No. The whole process runs locally in your browser using JavaScript, so your CSV file and its data never leave your device.
Will it delete my header row?
No. When you enable the header option, the first row is always kept and is never compared or removed, even if identical values appear later.
Does it handle quoted values and commas inside fields?
Yes. The tool parses CSV with standard rules (comma delimiter, double-quote quoting, and internal quotes doubled), so fields containing commas, quotes, or line breaks are handled correctly.
Can I ignore uppercase and lowercase differences?
Yes. Turn on the ignore case option and values like "Ada" and "ada" are treated as the same, so those rows are counted as duplicates.
About this tool
Free online tool to remove duplicate rows from a CSV file. Dedupe by whole row or one column, with case-insensitive matching. 100% in your browser, no uploads.