Remove Duplicate Lines

Remove duplicate lines from text lists, lists of URLs, or email rosters while preserving original order or sorting alphabetically.

Summary:A duplicate line remover cleans large text lists by filtering out repeated rows. It supports case-insensitive matching, empty line removal, and original row order preservation.
Removed 0 duplicate(s)

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How to Use Remove Duplicate Lines

Follow these steps to use the Remove Duplicate Lines: 1. Paste your list or log document (one item per line) into the editor. 2. Configure settings to ignore trailing spaces or empty lines. 3. Click the deduplicate trigger to clear repeating list elements. 4. Review the clean list of unique lines and the duplicate count statistics. Paste or type your text to process it instantly. This tool processes your entered text locally in your browser.

Remove Duplicate Lines Formula / How It Works

The tool splits the text input into an array of lines, passes the array through a unique JavaScript Set object, and recombines the lines.

Formula:Splits text by newline characters, passes arrays to JS Set constructor, and joins lines back.
Example Calculation:

For example, let's look at a list containing: "apple", "banana", "apple", "orange", "banana" on separate lines. By entering these values into the tool, you will get a deduplicated list containing "apple", "banana", "orange" and a report of 2 removed duplicates instantly.

Frequently Asked Questions

Yes, lines must match exactly. "item" and "Item" are treated as distinct.

You can toggle whether to strip or keep empty whitespace lines.

By default, it maintains original order, but you can sort them if desired.

The process of filtering out repeating items to leave only unique values.

The browser can easily process thousands of lines of text.

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