Does it preserve the order of lines?

Yes, the tool keeps the first occurrence of each line and removes subsequent duplicates while maintaining original order.

Is it case-sensitive?

By default yes, but you can toggle case-insensitive mode to treat 'Hello' and 'hello' as duplicates.

Can it handle very large files?

The tool handles thousands of lines efficiently in your browser without uploading data to any server.

Remove Duplicate Lines

Remove duplicate lines from your text with one click.

By Mike Starr·Last reviewed: August 2026

Result

Output will appear here...

About Remove Duplicate Lines

The Duplicate Line Remover identifies and eliminates repeated lines from your text. This is invaluable for cleaning up data lists, email lists, log files, CSV data, and any text where duplicates need to be removed quickly and accurately.

How to Use This Tool

1Paste your text with duplicate lines into the input area.
2Click 'Remove Duplicates' to clean your text.
3Choose whether to be case-sensitive or case-insensitive.
4Copy the cleaned result to your clipboard.

Benefits of This Tool

Instantly removes all duplicate lines

Case-sensitive and case-insensitive modes

Shows how many duplicates were removed

Perfect for cleaning data and email lists

Frequently Asked Questions

Glossary

Duplicate Content

Substantially identical content that appears on two or more URLs.

Keyword Stuffing

The practice of overloading content with keywords in an attempt to manipulate rankings.

Word Count

The total number of words in a piece of text.

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