Remove duplicate lines
Keeps the first time a line appears and drops later copies. Order of first-seen lines is unchanged.
How to use the Remove duplicate lines
What does the Remove duplicate lines do?
Paste a list and drop duplicate lines; It applies this page-specific rule: each line is compared after optional trim.
Which inputs does this tool use?
To paste a list and drop duplicate lines, enter Lines; keep every value in the same example; the page then updates the result from the current values; Start with a familiar case covered by this rule - Blank lines: consecutive blanks collapse only if you tick “drop blank lines” - so the expected result can confirm the settings.
How should the tool result be read?
For a result intended to paste a list and drop duplicate lines, blank lines: consecutive blanks collapse only if you tick “drop blank lines”; read lines together with the original lines rather than as an isolated answer, and confirm that its units or structure match the intended use.
Does it sort?
When the goal is to paste a list and drop duplicate lines, no.
Windows vs Unix line endings?
When using the page to paste a list and drop duplicate lines, both are split correctly.
Limits and accuracy
When using this tool to paste a list and drop duplicate lines, the result covers the stated calculation and supplied values, not every real-world factor; check the result in its intended destination before relying on it for important work; keep lines until the output has been checked in its intended destination. For a repeatable check when you need to paste a list and drop duplicate lines, record Lines alongside the final output and selected options. A known example using lines can confirm how the page will paste a list and drop duplicate lines. While trying to paste a list and drop duplicate lines, read the status message before copying or downloading because it can identify an incomplete or unsupported Lines.
How this works
Each line is compared after optional trim. With “ignore case” on, “Apple” and “apple” are the same line; the first spelling is kept.
Blank lines: consecutive blanks collapse only if you tick “drop blank lines”. Otherwise an empty line is a value and the second empty line is a duplicate.
Nothing is uploaded. Large pastes are fine until the browser tab complains.
Frequently asked questions
Does it sort?
No. Use the sort-lines tool, then this one, if you want sorted unique.
Windows vs Unix line endings?
Both are split correctly.
Whitespace only differences?
Trim is on by default.