Duplicate Line Remover: remove repeated lines instantly

A duplicate line remover scans a list and deletes every repeated entry, keeping only the first occurrence of each unique line in its original order. It's the fix for lists that have picked up repeats — merged spreadsheet exports, combined email lists, or keyword lists pulled from several sources — without manually scanning line by line.

This duplicate line remover online works on any text with one item per line: email addresses, URLs, keywords, product codes, names, log entries, or rows copied out of a spreadsheet. Paste the text, click Remove duplicates, and copy the clean result. It's free, there's no sign-up, and everything happens in your browser.

How to use the duplicate line remover tool

Paste your list into the "Your list" box, with one item per line. Choose whether to ignore case and whether to trim whitespace (trimming is on by default), then click Remove duplicates. The cleaned list appears in the Result box along with a count of how many duplicate lines were removed. Click Copy to grab the result. Your original list stays in the top box, so you can change the options and run it again to compare.

Why duplicate lines show up

Duplicates usually sneak in when data is combined from more than one place: two exports merged into one file, a list copied twice by accident, or the same keyword added by two different people. They're easy to miss by eye in a list of any real size, and a single repeated row can throw off a count, a mail merge, or an import.

How the ignore-case and trim options work

Two toggles control how strictly lines are compared. "Ignore case" treats differently-capitalized duplicates — like "Email" and "email" — as the same line, which matters when a list was assembled from sources with inconsistent capitalization. "Trim whitespace" ignores accidental leading or trailing spaces when comparing, since a line with a stray trailing space would otherwise be treated as unique even though it reads identically. Both options only change how lines are compared: the line that's kept is always the original first occurrence, exactly as you pasted it.

The original order is always preserved

Some tools sort your list alphabetically as a side effect of removing duplicates. This one doesn't. Each unique line stays exactly where it first appeared, and only the later repeats are removed. That matters when the order carries meaning, such as a ranked keyword list, a sequence of steps, or log lines in time order. If you do want a sorted list, sort it first in a spreadsheet or code editor, then paste it here.

A text duplicate line remover for any kind of data

Because it works line by line, this text duplicate line remover is useful for far more than simple lists. Marketers use it to dedupe email lists before importing them into a newsletter tool. SEO specialists merge keyword exports from several tools and remove the overlap. Developers clean up lists of URLs, IP addresses, or log lines. Teachers and students tidy up reading lists and bibliographies. If you can put each item on its own line, the tool can dedupe it.

How to remove duplicate lines from a PDF

Looking for a PDF duplicate line remover? You don't need to upload the file. Open the PDF, select the text you want (Ctrl+A on Windows or Cmd+A on Mac selects everything in most readers), copy it, and paste it into the box above. PDFs often copy with extra spaces at the start or end of lines, so leave "Trim whitespace" on to make sure those lines still match. Scanned PDFs, where each page is an image, can't be copied as text and need OCR first.

Duplicate lines vs. duplicate words

This tool compares whole lines. Two lines only count as duplicates if they match completely, after any ignore-case or trim options are applied. It won't remove repeated words inside a sentence or spot near-duplicates like "New York" and "New York City". If your data has extra spaces in the middle of lines, run it through ourwhitespace removerfirst, then dedupe it here.

Example: cleaning up an email list

Say you've exported subscribers from two sign-up forms and combined them into one list. Some people signed up twice, some with different capitalization (Jane@Example.com and jane@example.com), and some rows have a trailing space from the spreadsheet. Paste the list in, tick Ignore case, leave Trim whitespace on, and click Remove duplicates. Every repeat disappears, the first version of each address stays in its original position, and the counter tells you exactly how many duplicates were removed.

Is my list private?

Yes. Duplicate removal runs in your browser using JavaScript, so your list never travels to a server. That matters for email lists, customer data, and anything else you'd rather not paste into a website that uploads it. Your list is saved in your browser's local storage so it's still there if you refresh, and clicking Clear removes it.

Paste in a list of any size — a handful of lines or tens of thousands — and get a clean result in one click, with a count of exactly how many duplicate lines were removed. Everything runs locally in your browser, so your list is never uploaded.