Remove Duplicate Lines
Paste a list and strip out the repeated lines — keeping the first copy of each — with case and sorting options.
About this tool
Duplicates creep into every list that has been merged, exported or maintained by hand: email lists, keyword lists, inventory, survey responses, log extracts. This tool keeps the first occurrence of each line and deletes the rest, then reports exactly how many duplicates it removed.
By default, matching ignores letter case and trims stray spaces — because “Apple”, “apple” and “ Apple ” are the same item in almost every real list. Turn on case-sensitive matching if capitals matter, and sort the result if you want a clean A–Z output. The processing is done in your browser, which matters when the list is customer data: nothing is uploaded.
How to use it
- Paste your list into the box, one item per line.
- Adjust the options — trim and case-insensitive matching are on by default.
- Copy the cleaned list from the result box.
Frequently asked questions
Does it keep the first or last occurrence?
The first. Lines keep their original order unless you switch on sorting.
Are blank lines removed?
By default, yes — empty lines are dropped from the result, so the output is a clean list. If blank lines separate groups in your list, tick “Keep blank lines” and a single blank separator is preserved in its place.
Can it handle large lists?
Yes. Because it runs locally in your browser, lists of tens of thousands of lines are processed instantly, and size is limited only by your device. Use the Download button to save the cleaned list as a .txt file instead of copying it.