Remove Duplicate Lines
Paste a list to strip out repeated lines. The first occurrence of each line is kept, so the original order survives.
Everything runs in your browser, so even long lists stay private and the tool works with the network switched off.
Frequently Asked Questions
Does it keep the original order?
Yes. The first time a line appears it is kept in place; later copies are removed. If you want the result sorted as well, run it through the sort tool afterwards.
What does case sensitive mean here?
With it on, Apple and apple count as two different lines. With it off, they are treated as the same and only the first is kept.
Why trim spaces around lines?
Because a line with a trailing space looks identical but is technically different. Trimming catches those near-duplicates, which are extremely common in lists copied out of spreadsheets.
How many lines can it handle?
Hundreds of thousands. Deduplication uses a hash set, so it stays fast even on very large lists — the practical limit is your browser memory.