Remove Duplicate Lines Online
Paste your text and remove all duplicate lines instantly with flexible options
Deduplication Features
Flexible options for any text cleaning task
Choose between case sensitive and case insensitive comparison to match your exact deduplication requirements.
Duplicates are removed instantly regardless of list size. See the count of removed lines and unique lines remaining.
browser-side workflows run locally in your browser. Your text is never sent to or stored on any server.
About This Tool
This tool removes repeated lines from a block of text, leaving one copy of each. It is useful for cleaning lists such as email addresses, URLs, keywords, or log entries where duplicates have crept in from copying and merging sources.
The tool typically offers case-sensitive and case-insensitive matching, because whether Apple and apple count as the same line depends on your data. It preserves the original order of first appearance, so the deduplicated list still reads in the sequence you built it, rather than being sorted and reshuffled.
Whitespace is a frequent trap: two lines that look identical can differ by a trailing space or a tab, so they escape a naive duplicate check. A good deduplicator trims each line before comparing, or offers that as an option, so visually identical entries collapse as expected. Preserving first-appearance order rather than sorting also matters when the sequence of the list carries meaning. Trailing spaces and tabs are a common trap, since two lines that look identical can differ by invisible whitespace and so escape a naive match, which is why trimming each line before comparing catches duplicates that would otherwise slip through.
How to Use It
- Paste the text or list with duplicates.
- Choose whether matching should ignore case.
- Copy the cleaned list with each line appearing once.