List Comparison Tool
Paste two lists, one item per line, and instantly see which items appear in both, which are only in List A, and which are only in List B.
Frequently Asked Questions
- How do I compare two lists online?
- Paste one list into the List A box and the other into List B, one item per line, then click Compare. You get three results: items in both lists, items only in A, and items only in B — each with a count and a copy button.
- Is the comparison case-sensitive?
- By default no — "Apple" and "apple" are treated as the same item. Turn off the case-insensitive option if capitalization should matter in your comparison.
- What does the trim whitespace option do?
- It strips spaces and tabs from the start and end of every line before comparing, so "apple " and "apple" match. It is on by default because trailing spaces from copy-paste are a very common cause of false differences.
- How are duplicate items handled?
- With "Ignore duplicates" on, repeated items within a list are collapsed so each unique item appears once in the results. Turn it off to keep every occurrence from the source lists.
- What can I use this for?
- Anything that involves reconciling two sets of items: checking a bibliography against in-text citations, comparing email or attendee lists, diffing keyword sets, or finding which references two papers share.