Duplicate Line Remover
Paste a list — keywords, emails, log lines, CSV rows, URLs — and strip out every duplicate while keeping the first-seen order. Cleaned output appears instantly with a count of what was removed, and one click copies the result.
This is the everyday data-cleaning chore: deduplicating keyword exports before analysis, merging mailing lists, tidying SQL results, or trimming a wordlist. Everything runs locally in your browser — your data never touches a server, which matters when the list contains something private.
How to use
- Paste your text or list into the input box.
- The cleaned output appears instantly — duplicates removed, first-seen order kept.
- Check the removed-lines count, then hit Copy to take the result.
Frequently asked questions
How does it decide which duplicate to keep?
It keeps the first occurrence and drops every later repeat — so the order of your original list is preserved. This matters for ranked lists, logs and timelines.
Does it treat lines that differ only by spaces as duplicates?
Each line is compared exactly, including leading and trailing spaces. If your data has messy whitespace, trim the lines first — case is also preserved (Apple and apple are different).
Is there a size limit?
The practical limit is your browser tab's memory — lists of hundreds of thousands of lines process in a second or two. Everything runs locally, so there is no upload bottleneck.
Is my data uploaded anywhere?
No. The deduplication runs entirely in your browser with JavaScript. Nothing is transmitted or logged — you can disconnect from the internet and it still works.