Remove Duplicate Lines
Remove duplicate lines, keeping the first of each in order.
How this calculation works
The tool keeps the first time each line appears and drops later repeats, leaving the remaining lines in their original order. Case-insensitive mode treats lines that differ only in capitalisation as duplicates.
What the results mean
- Order preserved
- Unlike a sort-and-unique, this keeps your lines in the order they first appeared.
- Ignore case
- Treats "Apple" and "apple" as the same line, keeping whichever came first.
Frequently asked questions
Does this sort my lines?
No, deliberately. It removes duplicates while keeping the original order, because sorting would destroy information you may care about. If you want sorted output, sort first and then deduplicate.