Does it keep the original order?

Yes. The first time each line appears is kept exactly where it was, and only the later repeats are removed. This is different from sorting and deduping, which would reorder everything; here your list stays in the order you pasted it.

What does the case-sensitive toggle change?

With case sensitivity off, "Apple" and "apple" count as the same line and only one is kept. With it on, they are treated as different lines and both survive. Choose based on whether capitalisation is meaningful in your data.

Are blank lines and spacing handled?

You can trim leading and trailing spaces before comparing, so lines that differ only by stray spacing are treated as duplicates. Blank lines can be kept or collapsed depending on the option you pick, so the result is as tidy as you want.

Is my text sent to a server?

No. Everything runs locally in your browser. Your text is read and processed on your own device, nothing is uploaded, and nothing is logged or stored. Once the page has loaded, it keeps working even if you go offline.

Remove Duplicate Lines

Remove duplicate lines from a list and keep only the first appearance of each, in the original order. Toggle case sensitivity and see how many lines were removed. A free deduplicator that runs in your browser, with nothing uploaded.

No sign-up, ever
100% free
Nothing uploaded
Works offline after first load
No limits, no email wall

Read the guide: How to Remove Duplicate Lines

Case-sensitiveTrim spacesDrop blank lines

Your lines

Unique lines

How to use it

1
Paste your lines

Drop in a list, one item per line.
2
Choose your options

Decide whether matching should be case-sensitive and whether to trim surrounding spaces before comparing.
3
Get the clean list

Duplicates are removed in place, the order is preserved, and you see how many were taken out.

When it comes in handy

Mailing and contact lists

Strip repeated email addresses or names before importing into a tool that charges per contact.

Keyword and tag lists

Clean a list of keywords, tags or URLs so each one appears only once.

Log and data tidying

Collapse repeated lines from logs or exports into a unique set you can actually read.

Instant & 100% private — nothing is uploaded

Every keystroke is handled right here in your browser. Your text is never sent to a server, so there is no sign-up, no email wall, and no length cap from us. Load the page once and it keeps working even if you go offline.

Frequently asked questions

Does it keep the original order?: Yes. The first time each line appears is kept exactly where it was, and only the later repeats are removed. This is different from sorting and deduping, which would reorder everything; here your list stays in the order you pasted it.
What does the case-sensitive toggle change?: With case sensitivity off, "Apple" and "apple" count as the same line and only one is kept. With it on, they are treated as different lines and both survive. Choose based on whether capitalisation is meaningful in your data.
Are blank lines and spacing handled?: You can trim leading and trailing spaces before comparing, so lines that differ only by stray spacing are treated as duplicates. Blank lines can be kept or collapsed depending on the option you pick, so the result is as tidy as you want.
Is my text sent to a server?: No. Everything runs locally in your browser. Your text is read and processed on your own device, nothing is uploaded, and nothing is logged or stored. Once the page has loaded, it keeps working even if you go offline.