How to compare two lists
- Paste the first list into List A and the second into List B — one item per line.
- Pick a mode: only in A, only in B, in both or all unique.
- Copy the result, or download it as a
.txtfile. The result updates as you type.
What each mode gives you
- Only in A — items that exist in the first list but not the second. This is the classic “what did we lose?” check (old list vs new list, expected vs exported).
- Only in B — items that are only in the second list: new signups, new SKUs, entries added since the last export.
- In both — the intersection. Use it to confirm that two sources really overlap before you merge them.
- All unique — the union of both lists with duplicates removed, useful for building one combined master list.
Matches are compared as whole lines
Each line is one item, and an item matches only if the whole line matches — this is not a substring or diff search. By default Ignore case and Trim spaces are on, so Apple, apple and apple are the same item. Turn them off for a strict, character-by-character comparison; turn on A → Z if you want the result sorted rather than in pasted order.
Pasted a spreadsheet row instead of a column? If a list arrives with no line breaks but tabs or commas, it is split on those separators for you.
Lists that work well here
Email lists before and after a cleanup, keyword lists from two tools, product SKUs from two exports, allow/block lists, invite lists, tag lists, redirect maps, or two versions of the same CSV column. Because the page only compares lines of text, the content type does not matter.
Private by design
Nothing is uploaded: the comparison runs in JavaScript inside this tab, so it is safe for customer data, internal lists and anything you would not paste into a web service. The lists you paste can be remembered locally on this device so you can pick up where you left off — Forget next to the Recent chips wipes that, and none of it is ever sent to a server.
Need duplicates gone first?
To clean up one list instead of comparing two, use remove duplicate lines, dedupe a list online, or keep unique lines only. Comparing email lists before a merge? Dedupe the email list first, then compare.