Free Remove Duplicate Lines Tool — Dedupe Text Online
Paste a list, remove duplicate lines instantly — with case-sensitive, whitespace-trim, and blank-line options.
How it works
Paste your text
Paste a list or any text with duplicate lines into the input.
Set options
Choose case sensitivity, whitespace trimming, and whether to keep blank lines.
View results
Deduplicated output appears instantly in the result panel.
Copy or download
Copy the clean list to clipboard or download as a text file.
Common use cases
Email list cleaning
Remove duplicate email addresses from exported lists before sending campaigns.
Keyword list deduplication
Clean up SEO keyword lists or tag lists that contain repeated entries.
Code cleanup
Remove duplicate import statements, CSS rules, or configuration entries.
Data normalisation
Deduplicate exported CSV rows or database query results before processing.
Frequently asked questions
Is this duplicate line remover free?
Yes — completely free, unlimited text, no account required.
What does the case-sensitive toggle do?
When ON, "Apple" and "apple" are treated as different lines. When OFF (default), they are considered duplicates.
What does "Trim whitespace" do?
When ON, leading and trailing spaces are stripped before comparing, so " hello " and "hello" are treated as duplicates.
Will it preserve line order?
Yes — the first occurrence of each unique line is kept, and original order is preserved.
Is my text sent to a server?
No — deduplication runs using JavaScript Set in your browser. Your text never leaves your device.
Does it work on mobile?
Yes — fully responsive and works on iOS and Android browsers.