Remove Duplicate Lines

Remove duplicate lines — keep the first copy, preserve the order.

Processed locally – files never leave your device

Your lines (one per line)

Removes duplicates live as you type. Nothing is uploaded — the check happens in your browser.

Case-sensitive Ignore blank lines

Unique lines

0Input lines

0Unique lines

0Removed duplicate lines

Next: try Word Counter — Count words, characters, sentences, paragraphs, reading time.

Pasted a list with repeated lines, or merged two files and ended up with the same entries twice? This free tool removes duplicate lines in one step: it keeps the first occurrence of each line, deletes every later copy, and preserves the original order of everything that remains. You also get a count of how many lines were removed.

Everything runs in your browser, so your lists are never uploaded. Two toggles control the details: case-sensitive matching is on by default, and blank lines are ignored by default. To check the length of a cleaned list, use the Word Counter, and to tidy its capitalisation try the Lowercase Converter.

How to use

Paste or type your lines into the input box above — one item per line.
Choose the options: case-sensitive matching and ignoring blank lines are both on by default.
Watch the cleaned list appear live, with a count of removed lines. Use Copy to copy it, or Clear to start over.

Why use Toolsvine

De-duplicating a list should not mean uploading it to a server, and with Toolsvine it does not. The check is done by JavaScript on your own device, so mailing lists, customer names and private notes never leave your computer. It is free, has no limits, and works offline once the page has loaded.

How duplicate removal works

The tool reads your text line by line, from top to bottom, and remembers every line it has already seen. The first time a line appears it is kept; every later appearance of the same line is removed. Because lines are processed in order, the cleaned list keeps the original sequence — nothing is sorted, so a ranked list stays ranked.

The two options, explained

Option	On (default)	Off
Case-sensitive	“Apple” and “apple” count as different lines	They count as the same line; the first spelling is kept
Ignore blank lines	Empty lines are dropped from the result	Blank lines are treated as lines; only the first is kept

Case-sensitive matching is the safe default for lists of names, codes and file paths, where capitalisation matters. Turn it off when you are cleaning a list of words or tags and “Apple” and “apple” really are the same entry. Ignoring blank lines is usually what you want after merging files, because pasted text often carries stray empty lines that add nothing.

What counts as a duplicate

Two lines count as duplicates only when they match exactly, character for character, including spaces. “Apple” and “Apple ” — with a trailing space — are different lines to this tool, as are “New York” and “New York” with a double space. If a list still has near-duplicates after cleaning, check for trailing spaces or extra spaces inside the lines.

Frequently asked questions

Is my text uploaded anywhere?

No. The check runs entirely in your browser with JavaScript. Your text never leaves your device, and the tool keeps working if you go offline after the page loads.

Which copy of a duplicate line is kept?

The first occurrence. Later copies are removed, and the order of the remaining lines is unchanged, so a ranked list keeps its original sequence.

What is the difference between case-sensitive on and off?

With case-sensitive on, “Apple” and “apple” are different lines and both are kept. With it off, they count as the same line and only the first spelling is kept. Use off for word and tag lists, on for names, codes and file paths.

What happens to blank lines?

With “ignore blank lines” on, empty lines are dropped from the result. With it off, blank lines are treated like any other line: the first blank line is kept and later ones are removed as duplicates.

Does it sort my list?

No. The tool never sorts. It only removes later copies of lines already seen, so the output order is exactly the input order minus the duplicates.

Why are two lines that look identical both kept?

They probably differ invisibly — a trailing space, a double space inside the line, or a different capital letter. With case-sensitive matching on, “Apple” and “apple” are different lines too. Turn the toggle off or trim the spaces and try again.