Remove Duplicate Lines

Got a list with duplicates? Paste it here and watch them vanish. This keeps the first occurrence and removes repeats while preserving your original order: super handy when you're cleaning up email lists, data exports, or combined logs from multiple sources. I built this after spending 20 minutes manually scanning through a 500-line list looking for dupes. Never again. It's case-sensitive by default (so "Test" and "test" are different), but you can toggle that off if needed. Works instantly even with thousands of lines. One gotcha: empty lines count as duplicates too, so it'll remove those unless you want them. Great for SQL inserts, removing duplicate URLs, or just making messy data usable.