Text Tools
Find unique lines in two lists.
Paste two lists and get just the lines that appear in only one of them, or only in list A, or only in list B. Shared lines are left out.
Inputs
Result
Paste both lists, or press Load example. Results update as you type.
How finding unique lines in two lists works
This tool answers one question: which lines appear in only one of the two lists? A line that is in both lists is left out. What remains is the symmetric difference of the two lists: items that are in A or in B but not in both.
Choosing what to show
- In only one list returns the lines unique to A followed by the lines unique to B.
- Only in list A returns what A has that B lacks, such as customers who left or files that were deleted.
- Only in list B returns what B has that A lacks, such as new sign-ups or added files.
Lines are compared as exact text after the clean-up options you pick (trim, skip empty, ignore case, Unicode normalization), so Date and date only match when Ignore case is ticked. A line repeated inside one list is counted once. CRLF and LF line endings both work, and blank lines are skipped by default.
If you want all four groups at once (in both, only A, only B, all), use Compare Two Lists. To compare two passages of text rather than lists, use the diff checker. To compare JSON, use JSON Diff.
Sources
- Symmetric difference (items in either set but not both)
- Unicode Standard Annex #15: Unicode Normalization Forms
- MDN: String.prototype.normalize()
Set-operation definition, Unicode normalization annex and MDN reference retrieved October 2026.
Find unique lines FAQ
How do I find unique lines in two lists?
Paste the lists into boxes A and B, one item per line. With the default setting, the result is every line that appears in only one of the lists. Lines found in both are excluded.
What is the difference between unique lines and duplicate lines?
Here, a unique line is one that appears in just one of the two lists. A line found in both lists is shared, not unique. To remove repeats inside a single list instead, use the Remove Duplicate Lines tool.
How do I find lines in one file that are not in another?
Paste the first file into A and the second into B, then choose Only in list A to see lines the first has and the second lacks, or Only in list B for the reverse.
Does it handle Windows line endings?
Yes. CRLF, CR and LF line breaks are all treated as the same separator, so lists copied from Windows and Mac files compare cleanly.
Can I sort the result?
Yes. Choose A to Z or Z to A in the Order menu, or keep the order in which items first appeared.
Is my list uploaded?
No. The comparison runs in your browser and your lists are not sent to a server. The page itself still loads the site analytics and advertising scripts, so avoid pasting anything you would not paste into a normal web page.