How to use
Paste your list into the input box, one value per line, and the result with duplicate lines removed appears in the output box. There is no button to press, and the result keeps updating as you edit the input. Use the copy button to grab the result.
What counts as the same line
By default, two lines only count as duplicates when their content matches exactly, character for character — a single extra space or a different letter case makes them different lines. The options below let you loosen that comparison.
- Ignore case: treats
Apple,appleandAPPLEas the same value, and keeps only the spelling that appeared first. - Trim whitespace before comparing: ignores leading and trailing spaces and tabs when comparing, so
hong@test.comandhong@test.comcount as the same value. This only affects the comparison — the whitespace on the lines that remain in the result is left untouched. - Ignore empty lines: leaves empty lines (or, with trimming on, lines that contain only whitespace) out of both the result and the duplicate check. With this off, several empty lines are treated as duplicates of each other and only one is kept.
- Show removed lines only: shows the duplicate lines that get removed instead of the lines that are kept, so you can review what was dropped.
For each unique value, the first occurrence is kept and every later occurrence of the same value is removed. The number of lines actually removed is shown above the result.
When this is useful
Use it when you need to strip out repeats after merging email or username lists from several files, cleaning up a list of values copied from a spreadsheet with repeated entries, or combining attendee or contact lists from different people. It is built for line-based lists, not multi-line paragraphs or tabular data where a single record spans several lines.
Privacy
Your input is processed entirely inside this browser and is never sent to a server or stored. Closing the page clears whatever you pasted.