Duplicate Line Remover
Paste text and instantly remove all duplicate lines, keeping only unique lines.
What Is the Duplicate Line Remover?
The Duplicate Line Remover is a fast, browser-based tool that scans your text and eliminates repeated lines, keeping only the first occurrence of each unique line. No data is sent to any server — everything is processed locally in your browser for complete privacy.
Whether you're cleaning up a CSV export, deduplicating a word list, or sanitizing log data, this tool saves time and reduces manual effort instantly.
How to Use This Tool
- Paste your text into the input box — each line is treated as a separate entry.
- Choose your options: toggle case sensitivity, whitespace trimming, empty line removal, and order preservation.
- Click Remove Duplicates to process the text instantly.
- Review the stats showing total, unique, and removed line counts.
- Copy the result to clipboard or download it as a .txt file.
Common Use Cases
- Cleaning up keyword lists for SEO or PPC campaigns
- Deduplicating email lists or contact lists
- Removing repeated entries from log files or exports
- Sanitizing data before importing into databases
- Filtering out repeated words or phrases from writing
- Processing code output, test results, or terminal logs
Frequently Asked Questions
Is my data safe when using this tool?
Yes. All processing happens entirely in your browser using JavaScript. No text is ever uploaded to a server, stored, or shared. Your data stays completely private.
What does "case-sensitive comparison" mean?
When enabled, "Apple" and "apple" are treated as two different lines and both are kept. When disabled, they are considered duplicates and only the first occurrence is kept.
What does "trim whitespace" do?
When enabled, leading and trailing spaces are stripped from each line before comparison. So " apple " and "apple" would be treated as duplicates. The output will contain the trimmed versions of each line.
Will the original order of lines be preserved?
Yes, by default the "Preserve original order" option is checked. The first occurrence of each line appears in the output in the same order it appeared in the input. You can uncheck this if order doesn't matter.
Is there a limit to how much text I can process?
There is no hard limit imposed by the tool. However, very large files (millions of lines) may be slow depending on your device's processing power, since it runs entirely in your browser.
Can I use this tool on mobile devices?
Absolutely. The tool is fully responsive and works on smartphones and tablets. You can paste text, adjust options, and copy or download the result on any modern mobile browser.