Remove Duplicate Lines

The tool reads your text line by line and keeps only the first occurrence of each line, dropping any later repeats. The result is a list with every line appearing just once.

Yes. Duplicates are removed while the first appearance of each unique line stays in its original position, so the overall order is preserved.

With ignore-case on, lines that differ only in capitalisation are treated as the same, so Hello and hello count as duplicates. Without it, casing differences make lines distinct.

Trim strips leading and trailing whitespace before comparing lines, so two lines that look identical but differ by stray spaces are recognised as duplicates. It prevents invisible whitespace from defeating the de-duplication.

The keep-blank option controls whether empty lines are preserved in the output or collapsed away. Turn it on to retain spacing, or off to drop empty lines entirely.

No. All processing runs client-side in your browser, so the text you paste is never uploaded or stored.

Yes. It compares every line against all earlier lines, so repeated entries are removed no matter how far apart they appear in the list.