Remove Duplicate Lines
Great for email lists, keywords and names — the first occurrence stays in its original position.
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Remove duplicates, keep the order
Paste a list with one item per line. Duplicates are removed instantly and the first occurrence of each line stays where it was — unlike sorting tools, the order of your list doesn't change.
- Ignore leading/trailing spaces — “apple” and “apple ” count as the same line.
- Ignore case — “John@example.com” and “john@example.com” count as the same (useful for email addresses).
- Show only duplicated lines — find which items were entered more than once.
- Show only lines that appear once — items with no duplicates at all.
- Count occurrences — each line with its count, most frequent first, separated by a tab so it pastes into two spreadsheet columns.
Frequently asked questions
How long can the list be?
Tens of thousands of lines are processed instantly; it depends on your device's memory.
Can I dedupe by one column of a CSV?
This tool compares whole lines. For column-based work, use a spreadsheet's Remove Duplicates feature.
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