Monu Tools

Remove Duplicate Lines

Remove duplicate lines from a list or text, with options to ignore case, trim and sort.

How to use the Remove Duplicates

  1. 01

    Paste your lines or list.

  2. 02

    Choose whether to ignore case, trim, remove empty lines or sort.

  3. 03

    Copy the de-duplicated result.

What it does

This tool removes duplicate lines from any list or block of text. By default it keeps the first occurrence of each line in its original position and drops the later repeats, so the order you had is preserved.

It is the quick fix for messy lists: deduplicating an email or address list, cleaning an export, collapsing repeated log lines, or tidying a keyword list where the same term crept in several times.

The processing happens entirely in your browser, so even long lists are handled instantly and nothing you paste is uploaded.

How matching works

Matching is exact by default, comparing the whole line character for character. That makes it predictable: two lines count as duplicates only if they are truly identical, unless you loosen the rules with the options below.

Options you can combine

Trim ignores leading and trailing spaces, turning off case-sensitivity treats "Apple" and "apple" as the same line, and you can drop empty lines so blank rows do not survive.

You can also sort the result alphabetically if order does not matter and you would rather have a clean, sorted list than the original sequence.

Frequently asked questions

Does it keep the original order?

Yes. The first occurrence of each line is kept in its original position, unless you enable sorting.

How are duplicates matched?

Lines are compared exactly by default. Enable trim to ignore leading and trailing spaces, and turn off case-sensitivity to treat "Apple" and "apple" as the same.

Is my data private?

Yes. The processing happens entirely in your browser; nothing is uploaded.

Can it sort the lines too?

Yes. An option sorts the de-duplicated result alphabetically, if you prefer a clean sorted list over the original order.

Can it remove empty lines?

Yes. A toggle drops blank lines so they do not clutter the output alongside the de-duplication.

Is there a limit on how many lines?

There is no fixed limit. Because it runs in your browser, very large lists use more memory, but everyday lists are processed instantly.

Embed this tool

Add this tool to your own website. Copy the snippet below; it stays up to date automatically.

<iframe src="https://monu.tools/embed/en/remove-duplicate-lines" width="100%" height="640" style="border:1px solid #e5e5e5;border-radius:12px;max-width:680px" loading="lazy" title="Monu Tools"></iframe>

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