Remove duplicate lines from text instantly. Toggle case sensitivity and whitespace trimming. Optionally sort output alphabetically. See stats on total, unique, and removed lines.
LevnTools Duplicate Line Remover lets you analyze and transform text directly in your browser. Everything runs locally in your browser — your text and strings never leave your device. Unlike cloud-only alternatives that require uploads and accounts, this tool is completely free with no usage limits or watermarks. It is designed for writers checking word count and readability, students formatting essays and papers, developers manipulating string data — anyone who needs a fast, reliable text tool without the overhead of installing software. Just open the page and start working.
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When case-insensitive mode is enabled, "Hello" and "hello" are treated as the same line, and only the first occurrence is kept. In case-sensitive mode (the default), they are treated as different lines.
Yes. When "Trim Whitespace" is enabled, leading and trailing spaces are removed from each line before comparing. This means " hello " and "hello" would be considered duplicates.
Yes. Unless you enable "Sort Alphabetically," the tool keeps the first occurrence of each unique line in its original position. Duplicates are simply removed.
Yes. The tool handles thousands of lines efficiently. All processing happens in your browser with no upload or server round-trip required.