Remove duplicate lines from any text in seconds. Case-sensitive or insensitive, with options to sort, trim whitespace, remove blanks, and see exactly which duplicates were found.
Open Remove Duplicate Lines → free, no sign-inPasting data from multiple sources often leaves you with repeated lines — duplicate email addresses, repeated log entries, duplicate keywords, or redundant list items. This tool removes them in one click. It supports case-sensitive and case-insensitive matching, optional sorting, whitespace trimming, and blank-line removal, and shows you a list of which duplicates were found and how many times each appeared.
No tutorials. No learning curve. Open it and get started.
No server uploads. Everything runs locally in your browser. Your files and data never leave your device.
Completely free. No trial period. No premium tier for basic functionality. No account required. Use it as often as you need.
One job, done well. Remove Duplicate Lines was built to solve a specific problem cleanly. No feature bloat, no ads, no distractions.
Is the comparison case-sensitive?
By default yes, but you can switch to case-insensitive mode so "Apple" and "apple" are treated as the same.
Can I keep the last occurrence instead of the first?
Yes — toggle "Keep last occurrence" and the tool will discard the earlier appearances.
What does "trim whitespace" do?
It strips leading and trailing spaces from each line before comparing, so " hello " and "hello" are treated as the same.
Can I sort the result?
Yes — choose A→Z, Z→A, or no sort from the dropdown.
Is this free?
Yes — free with no sign-in.
Free. Instant. No sign-in. Open it and get the job done.
Open Remove Duplicate Lines on Doathingy.com →