The tool dedupes as you type and never modifies your input box, so you can toggle options and compare results without losing the original. By default two lines must match exactly, character for character. Ignore case treats Berlin and berlin as the same line; Trim whitespace ignores leading and trailing spaces or tabs, which catches the invisible duplicates that spreadsheets and log files love to produce. Blank lines are treated as structure, not data - they are never collapsed into each other unless you switch on Remove empty lines. Because everything runs client-side, it is safe for email lists, customer exports and unpublished keyword research.
Remove Duplicate Lines
Runs entirely in your browser - no upload, no sign-up.
Input text
Deduplicated text
Paste lines to remove the duplicates - the first occurrence of each line is kept
How do I remove duplicate lines from text?
Paste your text into the box above and every repeated line disappears instantly - the first occurrence of each line is kept, in its original order. Turn on Ignore case or Trim whitespace to catch near-duplicates like "Apple" vs "apple", then copy the cleaned list. Nothing is uploaded; deduplication runs entirely in your browser.
How to use
- 1Paste your lines. Type or paste any multi-line text into the left box - one item per line. Windows, Mac and Unix line endings all work.
- 2Pick how lines are compared. By default lines must match exactly. Toggle Ignore case to treat "Apple" and "apple" as duplicates, Trim whitespace to ignore leading and trailing spaces, or Remove empty lines to drop blanks.
- 3Copy the cleaned list. The deduplicated text appears live on the right, and the status bar shows how many duplicates were removed. Press Copy to put the result on your clipboard.
Who it's for
- SEO and marketing teams deduplicating keyword lists, backlink URLs or email addresses exported from several overlapping reports.
- Developers and sysadmins cleaning log output, environment lists or
.gitignore-style files without reaching forsort -u(which would also reorder everything). - Data analysts collapsing a pasted spreadsheet column to its distinct values before a lookup or a pivot.
- Writers and researchers merging reading lists, reference lists or brainstorm dumps from multiple documents into one clean list.
FAQ
Is my text uploaded anywhere?
No. Deduplication runs entirely in your browser using JavaScript - your lines never reach a server. That makes it safe for email lists, customer data, credentials files and anything else you would not paste into a random website form.
Is this duplicate line remover free?
Yes - completely free, with no sign-up, no download and no usage limits. It is a static page, so it also loads fast and keeps working on a flaky connection once open.
Is there a limit on how many lines I can paste?
No hard limit. Deduplication uses a hash set, so even lists with hundreds of thousands of lines process in well under a second on a typical laptop. The practical ceiling is your browser's memory, not the tool.
Which duplicate is kept - the first or the last?
The first. The tool scans top to bottom, keeps the first occurrence of each line in place and removes every later repeat, so the surviving order is exactly the order you pasted.
Does it remove duplicate lines without sorting them?
Yes - and that is the point. Command-line tricks like sort -u dedupe by sorting first, which scrambles ordered data. This tool preserves your original line order and only deletes the repeats.
How are empty lines handled?
Blank lines are treated as structure rather than data, so two empty lines are never merged into one. If you want a compact list with no blanks at all, switch on Remove empty lines and every empty or whitespace-only line is dropped.
Can it catch duplicates that differ only by spaces or capitalization?
Yes. Turn on Trim whitespace to ignore leading and trailing spaces and tabs, and Ignore case to match regardless of capitalization. With both on, " Apple" and "apple" count as the same line; the version kept is printed exactly as you pasted it.
Does it work with Windows (CRLF) line endings?
Yes. Windows (\r\n), Unix (\n) and old Mac (\r) line endings are all recognized when splitting, and the cleaned output uses standard Unix newlines, which every editor and spreadsheet accepts on paste.