How to use it
- Paste the list into the left box, one item per line.
- Turn on the options you need. The cleaned list appears on the right at once, with the number of removed and remaining lines under it.
- Press Copy.
How it works
The tool reads the text line by line and remembers every line it has already seen. A line seen before is skipped; a new one is added to the result. With “Ignore case” the comparison uses the lowercase form of each line; with “Ignore spaces at line ends” lines are trimmed first. Empty lines are either removed or kept untouched, depending on “Keep empty lines”.
Worked example
The list apple, banana, Apple, cherry, banana, apple (6 lines) becomes apple, banana, Apple, cherry: 2 lines removed, 4 left. With “Ignore case” on, “Apple” is a repeat of “apple” as well, so the result is apple, banana, cherry: 3 removed, 3 left.
Tips
Mailing lists often contain the same address with different capitals or a trailing space: turn both options on. A file from Windows works too - its line breaks are recognised, and the result uses plain line breaks.