About Remove Duplicate Lines
Clean lists and pasted text with exact control over case, whitespace, and empty lines. The first occurrence stays in place.
The tool compares complete lines rather than individual words. You decide whether capitalization, surrounding whitespace, and blank lines should affect equality, while the first matching line keeps its original position.
How to use it
- Paste or type the source text.
- Choose how case, whitespace, and blank lines should be handled.
- Copy or download the unique lines.
Common use cases
- Deduplicate email, SKU, domain, or keyword lists before importing them.
- Clean copied log values while preserving the order in which they first appeared.
- Normalize survey responses or spreadsheet columns without uploading the source data.
Worked example
A list containing apple, banana, apple becomes apple, banana.
Limitations and responsible use
- It does not detect near-duplicates, spelling variations, or semantically equivalent phrases.
- A line is treated as one value; embedded delimiters are not parsed as CSV columns.
- Very large pasted inputs still depend on the memory available to the browser tab.
Frequently asked questions
Does removing duplicates change the line order?
No. The first occurrence stays where it was and only later matches are removed.
Can Apple and apple be treated as the same value?
Yes. Disable case-sensitive matching to compare them as duplicates.