Merged two exports of the same mailing list? Pasted keywords from three research sessions into one file? Every combined list picks up repeats, and the traditional fix — a spreadsheet, a dedupe formula, a copy-paste back out — is heavy machinery for a one-column job.
Our duplicate line remover does it in the textarea, live on every keystroke:
- First occurrence wins — survivors keep their original position and original spelling, so your list comes back in the order you built it.
- Match your way — optional case-insensitive comparison, whitespace trimming, and empty-line removal, each toggle sitting in the URL so a bookmarked setup restores itself.
- Honest counters — lines in, unique lines out, and duplicates removed, so you can sanity-check the cleanup before copying.
- Private by design — your list is often names, emails, or SKUs, so it never leaves your browser and never touches the URL.
Ten thousand lines dedupe in a blink; the only limit is your browser’s memory.
Run a resource page for marketers or students? The tool is embeddable with one iframe.