Remove Duplicate Lines
Delete repeated lines and keep a unique list in its original order.
Remove Duplicate Lines Online
Paste a list and this tool deletes every repeated line, keeping only the first occurrence of each. It's the quickest way to get a unique list of emails, keywords, URLs, product codes, or any other line-based data.
How it works
- Paste your list or open a text/CSV file.
- Choose whether the comparison should ignore case and surrounding spaces.
- Copy or download the de-duplicated list. The tool also shows how many lines were removed.
Features
- Keeps the original order – unlike sorting tools, the first appearance of every line stays in place.
- Case-insensitive mode – treat "Apple" and "apple" as the same entry.
- Whitespace handling – ignore stray spaces that make identical lines look different.
- Fast on large lists – uses a hash set, so even 100,000+ lines are processed instantly.
Tips
Need the unique list sorted too? Run the result through Line Sorter or Alphabetical Order. To delete lines that contain a specific word, use Remove Lines Containing.
Frequently Asked Questions
Which copy of a duplicate line is kept?
The first occurrence is kept and every later copy is removed, so the original order of your list is preserved.
Are 'Apple' and 'apple' duplicates?
Only if you enable 'Ignore case'. By default the comparison is case-sensitive, so lines that differ only in capitalization are both kept.
Do spaces at the start or end of a line matter?
With 'Trim spaces' on (the default), leading and trailing spaces are removed before comparing, so ' cherry' and 'cherry' are treated as the same line.