Remove Duplicate Lines Tool
Remove duplicate lines online for free — with case and whitespace options and a removed-count. 100% in your browser.
100% private — runs entirely in your browser. Your text is never uploaded or logged.
Keeps the first occurrence of each line. “Ignore spaces” catches lines that only differ by invisible trailing whitespace. Processed locally — nothing is uploaded.
How to use the Remove Duplicate Lines Tool
- Paste your lines.
- Set case and whitespace options.
- See how many duplicates were removed.
- Copy the unique lines.
What you can use it for
- Remove duplicate emails or keywords
- De-duplicate a list ignoring case
- Clean a list with stray trailing spaces
- Dedupe and sort together
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Browse all free text tools →Frequently asked questions
Does it keep the first occurrence?
Yes — the first time a line appears it's kept; later duplicates are removed.
Is duplicate matching case-sensitive?
By default yes; turn on 'case-insensitive' to treat Apple and apple as duplicates.
Will trailing spaces stop duplicates being detected?
Not if you keep 'ignore leading/trailing spaces' on — it trims before comparing so near-identical lines still match.
Can I also remove blank lines?
Yes — 'remove blank lines' drops empty lines as well as duplicates.
Can I sort the result?
Yes — tick 'sort the result' to alphabetise the de-duplicated lines.