Remove Duplicate Lines

Cleaning up lists by removing repeats

Duplicate lines creep into lists all the time. Combining contact lists from two sources, exporting keywords from several tools, copying product codes from different sheets or collecting log output can all leave the same line appearing two or more times. Removing them by hand is tedious and error-prone, especially once a list runs into hundreds of lines.

This tool keeps the first time each line appears and removes later repeats, while leaving the original order unchanged. That matters when the order carries meaning, such as a ranked list or a sequence of steps. If you would rather have the list sorted as well, clean it here first and then use the sort tool. You can choose to treat 'Apple' and 'apple' as the same line, which is useful for email addresses and names typed inconsistently.

Hidden spaces are a common reason duplicates slip through other tools. Here, spaces at the start and end of each line are ignored by default, so ' Ravi' and 'Ravi ' count as the same entry. Double spaces in the middle of a line still make it different, so if you suspect those, run the list through the trim tool first to collapse them. For email lists, it also helps to convert everything to lowercase before cleaning, since addresses are not case-sensitive in practice. The count of removed lines gives a quick sense of how messy the original data was, and it is worth checking a few of the remaining lines before importing the result into a mailing tool or spreadsheet. Everything runs in your browser, so private contact lists never leave your device.