A QUICK WALKTHROUGH
How to use this tool
- Put one entry on each line.
- Choose which occurrence survives and whether comparison ignores case or surrounding spaces.
- Remove duplicates and check retained and removed counts.
How it works
Each line receives a comparison key. The key may be trimmed, normalized or lowercased, but the retained output keeps the original line text. First-occurrence mode preserves the order of first appearances. Last-occurrence mode preserves the order of the last appearances. A final newline is a terminator, not another empty entry.
A practical example
Start with
apple pear apple
What to expect
apple pear
Important considerations
This operates on lines, not CSV records. Quoted CSV values can contain real newlines; use the CSV deduplication tool for tables.
1 MiB per input. Input remains in page memory until you reset or leave. Copy and download actions are initiated by you. No tool input is sent to a processing service.
One more useful detail
Are Apple and apple duplicates?
Only when you enable Ignore letter case. The default comparison distinguishes them.