Remove Duplicate Lines
Remove duplicate lines from any text block and keep only unique lines. Paste a list, keyword set, email list, or any text — duplicates are removed instantly. Supports case-sensitive matching and whitespace trimming options. Free, no signup, works entirely in your browser.
Three steps. No setup.
Drop your content into the field above, or type directly into it. The tool starts working the moment you do — no button to press.
Everything is calculated locally in your browser as you type. No waiting, no uploading, no server involved.
Hit Copy to grab the result, or Download if the tool offers a file. Close the tab — nothing is stored.
Free, private, and built to last.
Remove Duplicate Lines is a free online tool that runs entirely in your browser. No data is sent to any server — your input stays private on your device and disappears the moment you close the tab.
It is designed to be fast, simple, and accessible to everyone — whether you are a developer, marketer, student, or business owner. No signup, no ads, no nonsense. Just the tool, ready when you need it.
Frequently Asked Questions
It scans your text line by line, identifies any lines that appear more than once, and removes the duplicates — keeping only the first occurrence of each line. The result is a list of unique lines in their original order.
In case-sensitive mode, 'Apple' and 'apple' are treated as different lines and both kept. In case-insensitive mode, they are treated as duplicates and only one is kept. Use case-insensitive mode for email lists and keyword lists where capitalisation should not matter.
Yes. Paste your email list or keyword list with each item on its own line. The tool removes exact duplicates instantly. Use case-insensitive mode to catch duplicates with different capitalisation (e.g. 'info@example.com' and 'Info@example.com').
Yes. The tool processes all deduplication in your browser without sending data to any server. It handles large text blocks quickly — suitable for lists of thousands of lines.
Yes, Notepad++ can remove duplicate lines using a plugin or the built-in TextFX plugin. However, this free online tool is faster for a one-off task — no software installation needed.