Paste your text below and get a clean, deduplicated version instantly. Choose from multiple options — case sensitivity, whitespace trimming, sorting, blank line control — all processed locally in your browser.
What this tool does
Deduplicate
Remove every repeated line, keeping the first or last occurrence as you choose.
100% Private
Your text never leaves your device. Everything runs in JavaScript, locally.
Advanced Options
Case insensitive mode, trim whitespace, sort output, remove blank lines, keep last occurrence.
Instant
Results update in real time as you type. No button to press.
Frequently asked questions
Is my text sent to a server?
No. The tool runs entirely in your browser using JavaScript. Your text never leaves your device.
What does case-insensitive mode do?
In case-insensitive mode, "Hello" and "hello" are treated as the same line. The first (or last, if selected) occurrence is kept.
What does trim whitespace do?
Trimming removes leading and trailing spaces from each line before comparing. " hello " and "hello" are then treated as duplicates.
Can I keep blank lines?
Yes. Enable "Keep blank lines" to preserve empty lines in the output. When disabled, all blank lines are stripped.
How do I remove duplicate lines in Excel or Google Sheets?
Export your column as plain text (one value per line), paste it here, deduplicate, then paste back. It is faster than the built-in dedup dialog for plain lists.