A duplicate line remover cleans lists and text by removing repeated lines, keeping only unique entries. Perfect for deduplicating email lists, keywords, URLs, and log files.
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Output
How to Remove Duplicate Lines
This tool instantly removes duplicate lines from any text, keeping only the first occurrence of each unique line in the original order.
Common Use Cases
Use the duplicate line remover to clean email marketing lists, deduplicate keyword research exports, remove repeated log entries, clean up database exports, and prepare clean CSV data. It handles lists of any size instantly in your browser.
Options Explained
Case-sensitive: When enabled, "Apple" and "apple" are kept as separate entries. When disabled (default), they are treated as duplicates. Trim whitespace: Removes leading/trailing spaces before comparing, so " hello " and "hello" are treated as duplicates. Remove empty lines: Filters out blank lines from the output.
FAQ
What does the duplicate line remover do?
It takes text with repeated lines and removes all duplicates, keeping only the first occurrence of each unique line. Useful for cleaning lists, log files, spreadsheet exports, and database dumps.
Is the comparison case-sensitive?
By default it is case-insensitive, meaning 'Hello' and 'hello' are treated as duplicates. Enable case-sensitive mode to keep both if you need to distinguish between them.
Does it preserve the original order?
Yes. The tool keeps lines in their original order, removing only the second and subsequent occurrences of any duplicate.
Is this tool free?
Yes, completely free. All processing happens locally in your browser — your data is never sent anywhere.
Can it trim whitespace before comparing?
Yes. Enable 'Trim whitespace' to treat lines that differ only by leading or trailing spaces as duplicates.