Remove Duplicate Lines Online
Paste your list of items (one per line) and instantly remove all duplicate entries. Keeps the first occurrence and strips the rest.
How to Use
Paste your text into the input area with one item per line, then click "Remove Duplicates". The tool trims whitespace from each line, removes exact duplicates using a Set-based algorithm, and filters out empty lines. The deduplicated result appears instantly below.
Why Choose This Tool?
This tool uses JavaScript's native Set data structure for O(n) deduplication, meaning it handles even very large lists (thousands of lines) in milliseconds. Everything runs locally in your browser with zero data transmission.
Frequently Asked Questions
Is the comparison case-sensitive?
Yes. "Apple" and "apple" are treated as different lines. If you need case-insensitive deduplication, use the Case Converter first to normalize your text.
Does it preserve the original order?
Yes. The tool keeps the first occurrence of each unique line and removes subsequent duplicates, preserving the original order.
Are empty lines removed?
Yes. Blank lines and lines containing only whitespace are automatically filtered out.
Is it completely free?
Yes. No hidden fees, no limits, no ads.
Is my data safe?
Absolutely. All processing happens locally in your browser. Nothing is sent to any server.