How to remove duplicate lines
Paste or upload line-based text, choose the comparison options, and review the deduplicated result in the output textarea.
- Paste text into the left textarea. You can also select Upload or drop a compatible text file anywhere on the page.
- Choose the comparison options:
- Enable Case sensitive to treat different capitalization as different lines.
- Keep Trim spaces before comparing enabled to ignore leading and trailing spaces when lines are compared. This option is enabled by default.
- Review the result in the output textarea. It displays text with no duplicated lines.
- Select Copy to copy the result or Download to save a plain-text output file.
Choose comparison settings
Use Case sensitive when capitalization should affect duplicate detection. When it is enabled, lines with different letter case are compared as different values.
Trim spaces before comparing changes the comparison key: lines that differ only in leading or trailing spaces are treated as duplicates. The first matching line is retained in the output with its original spacing. This option is enabled by default.
Limitations and local processing
Text processing is performed in the browser. Files selected through Upload or a page-wide drop are read as text in your browser; their contents are not uploaded to the tool.
The upload accepts .txt, .csv, .log and .md files (and text/plain files). If a file cannot be read, an error appears below the input and you can choose another file or paste text instead. The page does not define a maximum input size or line count, or provide a result count/statistics panel.
Frequently asked questions
How to remove duplicate lines from a list?
Paste the list into the input textarea, choose your Case sensitive preference, and optionally use Trim spaces before comparing. The tool filters repeated lines and places the result in the output textarea.
Is my data private during deduplication?
Text processing occurs locally in your browser. Uploaded files do not leave the browser, and list data is not uploaded to the tool's servers.