Remove Duplicate Lines

This tool processes text line by line in your browser. Each line is compared against all previously seen lines. When a duplicate is found, it's removed from the output.

The tool maintains the original order of your list, keeping the first occurrence of each unique line. A counter shows exactly how many duplicates were removed.

Optional features include case-sensitive matching (treating "ABC" and "abc" as different), alphabetical sorting of the output, and removal of blank lines.

Email list cleanup: Merge multiple subscriber lists and remove duplicate email addresses before importing to your email marketing platform.

Keyword research: Combine keyword suggestions from multiple tools and remove duplicates to build a master keyword list.

CSV data cleaning: Remove duplicate rows from exported data before analysis or import into a database.

Code refactoring: Clean up repeated import statements, CSS classes, or configuration entries.

Customer data deduplication: Merge customer lists from different sources and remove duplicate entries before CRM import.

URL list cleanup: Remove duplicate URLs from web scraping results or sitemap files.

Exact matching only: The tool removes exact duplicates. Lines that differ by even a single character (including trailing spaces) are considered unique.

Case sensitivity matters: By default, "Hello" and "hello" are treated as duplicates. Enable case-sensitive matching if you need to preserve both.

Large lists work fine: The tool handles thousands of lines, but very large lists (10,000+) may take a moment to process.

Whitespace is significant: A line with trailing spaces is different from the same line without. Use the Whitespace Remover tool first if needed.