Find and remove duplicate lines from your text
Find and remove duplicate lines from text instantly with our powerful online duplicate line remover. Perfect for cleaning up lists, removing redundant data, finding unique entries, or identifying repeated content. Process unlimited text completely free with advanced filtering options.
100% Free: No limits on text size, no watermarks, no subscriptions. Find and remove unlimited duplicate lines completely free.
Instant Processing: All duplicate detection happens in your browser in real-time. No waiting, no uploads, no delays.
Privacy Protected: Your text never leaves your device. All processing is done locally in your browser for complete privacy and security.
Flexible Options: Choose from multiple duplicate handling modes and customize comparison behavior to match your needs exactly.
Smart Detection: Automatically handles case sensitivity, whitespace trimming, and empty lines for accurate duplicate detection.
Remove All Duplicates: Keeps only unique lines. If a line appears multiple times, only the first occurrence is kept. Best for creating clean, unique lists.
Keep First: Similar to remove all - preserves the first occurrence of each line and removes all subsequent duplicates.
Keep Last: Keeps the last occurrence of duplicate lines and removes earlier ones. Useful when the last entry is most important.
Show Duplicates Only: Displays only lines that appear more than once. Perfect for identifying what content is duplicated.
Case Sensitive: When enabled, "Apple" and "apple" are treated as different lines. Disable for case-insensitive duplicate detection.
Trim Whitespace: Removes leading and trailing spaces before comparison. Prevents "apple" and " apple " from being treated as different.
Ignore Empty Lines: Skips blank lines in the comparison. Useful for text with irregular formatting or line breaks.
Email Marketing: Clean up mailing lists by removing duplicate email addresses before sending campaigns.
Data Analysis: Remove duplicate entries from datasets to ensure accurate statistics and analysis.
SEO Research: Deduplicate keyword lists when combining data from multiple sources.
Content Creation: Find repeated phrases or sentences in writing projects.
Programming: Remove duplicate imports, includes, or configuration entries from code files.
List Management: Merge multiple lists while removing overlapping entries.
How does duplicate detection work?
The tool compares each line of text with all other lines based on your selected options (case sensitivity, whitespace). Lines that match exactly are considered duplicates.
Is there a limit on text size?
No hard limit, but very large texts (millions of lines) may take longer to process depending on your device's performance.
Does this work with CSV files?
Yes! Paste your CSV data and the tool will process it line by line. Each row is treated as a separate line.
Can I preserve the original order?
Yes, the tool maintains the original line order while removing duplicates. The first occurrence position is preserved.
All duplicate detection and removal happens entirely in your web browser using JavaScript. Your text is never uploaded to our servers or any third party. This ensures your data remains completely private and secure while providing instant processing with no file size limits.
Convert text between UPPERCASE, lowercase, Title Case, camelCase, and more formats instantly.
Sort lines alphabetically, reverse order, shuffle randomly, or remove blank lines from text.
Find and replace text with support for case sensitivity, whole words, and multiple replacements.
Add prefixes or suffixes to each line of text. Perfect for batch formatting lists.
Count words, characters, sentences, and paragraphs with detailed statistics and reading time.
Repeat text multiple times with custom separators. Useful for testing and pattern generation.