Remove Duplicate Lines

What does Remove Duplicate Lines do?

Remove Duplicate Lines finds and removes repeated lines from your text, keeping only unique entries. It can also identify and show only the duplicates, helping you find repeated data quickly.

What is it used for?

• Data Cleaning: Remove duplicate entries from CSV files or databases
• Email Lists: Deduplicate mailing lists or contact exports
• Log Analysis: Find repeated error messages or events
• Code Cleanup: Remove duplicate imports or dependencies
• List Management: Clean up to-do lists, inventory, or any text list

Options

• Case Sensitive: Treat "Apple" and "apple" as different entries
• Trim Whitespace: Ignore leading/trailing spaces when comparing
• Remove Empty Lines: Filter out blank lines from the result
• Show Duplicates Only: Display only the repeated entries

How it works

Paste your text with one item per line, configure options, and click the button. The tool compares each line and keeps only the first occurrence of duplicates. All processing happens locally in your browser—your data stays private.