Clean
Duplicate Line Remover
Remove duplicate lines and optionally preserve order.
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Basic
What it is & how to use it
Clean lists, exports and keyword sheets by removing repeated lines. Optionally keep first-seen order.
How to use the Duplicate Line Remover
1) Paste a line-based list.
2) Remove duplicates (preserve order if offered).
3) Copy the cleaned list.
4) Diff against the original when stakes are high.
Intermediate
Formula & worked example
Unique set of lines; first occurrence wins when preserving order.
Whitespace-only differences may count as distinct unless trimmed by the tool options.
Advanced
Interpretation, edge cases & next steps
Case-sensitive duplicates can remain if casing differs.
Advanced: normalise case first when you want case-insensitive uniqueness; backup before bulk cleans.
Frequently asked questions
Order preserved?
When the option is on, first-seen lines stay in place.
Trim spaces?
Check tool options — trailing spaces can create false uniques.
Case sensitive?
Typically yes unless you normalise first.
Huge lists?
Very large pastes may slow the tab.
Stored?
Text stays in your browser session.
Deep guide
Read the full guide
Longer teaching, worked scenarios and mistakes — then jump back into this tool with example numbers.