What does the Remove Duplicate Lines tool do?
Exported lists — emails, keywords, URLs, IDs — accumulate duplicates fast. This tool removes them while preserving the original order, keeping the first occurrence of each line.
Case-insensitive mode treats “Apple” and “apple” as the same line when you need that.
How to use the Remove Duplicate Lines
- Paste your list, one item per line.
- Choose case-sensitive or not.
- Click Remove Duplicates and copy the result.
Frequently asked questions
Which duplicate is kept?
The first occurrence — order is preserved, later repeats are dropped.
Does it trim spaces before comparing?
No — “apple ” and “apple” differ. Run the Whitespace Cleaner first if needed.
How large a list can it handle?
Hundreds of thousands of lines comfortably — it is a single pass in your browser.
Is my list uploaded?
No — deduplication happens locally, which matters for email lists.