Explosion Tools

Duplicate Line Remover

Remove duplicate lines from text. Free, no signup, works in your browser.

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About Duplicate Line Remover

This tool removes duplicate lines from your text, keeping only unique entries. Choose to keep the first or last occurrence of each duplicate. Options include case-insensitive matching (so 'Apple' and 'apple' are treated as the same) and whitespace trimming before comparison. The tool preserves the original order of lines and shows how many duplicates were removed. Useful for cleaning up lists, email addresses, URLs, log entries, CSV data, and any line-separated content.

Frequently Asked Questions

Does this preserve the original order?
Yes. When keeping the first occurrence, lines appear in the order they were first seen. When keeping the last occurrence, lines appear in the order of their final appearance. The relative order is always preserved.
How does case-insensitive matching work?
When enabled, 'Apple', 'apple', and 'APPLE' are all considered the same line. The kept line retains its original capitalization — only the duplicates with different casing are removed.
What does the trim whitespace option do?
When enabled, leading and trailing spaces/tabs are ignored when comparing lines. So ' hello ' and 'hello' are treated as duplicates. The original whitespace is preserved in the output for the kept line.

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