Remove Duplicate Lines
Paste any list, one item per line, and get it back without repeats. Choose whether case and surrounding spaces matter, and sort the result if you like.
About this tool
Duplicate entries creep into email lists, keyword sets, log extracts and spreadsheet columns whenever data is merged from several sources. Removing them by hand is slow and error-prone; this tool keeps the first occurrence of every line and drops the rest, preserving the original order unless you ask for a sorted result.
Ignore case treats “Apple” and “apple” as the same line. Trim spaces ignores leading and trailing whitespace, so a line pasted with a stray tab still matches. Sorting uses natural order, so “item2” comes before “item10”. Everything runs in your browser and the text never leaves your device.
Frequently asked questions
- Which copy of a duplicate is kept?
- The first one. Later repeats are removed, so the order of the remaining lines matches the original unless you sort.
- Are lines with different capitalisation duplicates?
- Only if you enable Ignore case. By default the comparison is exact.
- Is there a size limit?
- No fixed limit. Lists of a few hundred thousand lines process in well under a second on a normal laptop.