Compare two email lists
Paste two email lists to see which addresses are in both, only in the first, or only in the second — with case-insensitive matching and duplicate detection.
Open the tool, then paste the sample input below. Everything runs locally in your browser.
The problem
You have two lists of email addresses — say subscribers and customers — and need the overlap, the unique entries on each side, and any duplicates. Doing it by hand is slow and misses case differences. A set comparison gives you the answer instantly.
Sample input
ada@example.com
ben@example.com
cleo@example.comBen@example.com
cleo@example.com
dan@example.comExpected output
In both: ben@example.com, cleo@example.com
Only in A: ada@example.com
Only in B: dan@example.comBen@example.com and ben@example.com match because the comparison is case-insensitive.
How to do it
- Paste the first email list.
- Paste the second email list.
- Choose case-insensitive matching.
- Compare the lists.
- Copy the in-both, only-in-A, or only-in-B set you need.
Common mistakes
- Case-sensitive comparison treating Ben@ and ben@ as different.
- Leading or trailing spaces around addresses.
- Duplicates within one list inflating the counts.
- Mixing names and emails in the same list.
- Different separators, such as commas versus newlines.
Related tools
Related guides
FAQ
How do I find emails in both lists?
Paste both lists and compare. The in-both set contains every address that appears in each list, matched case-insensitively if you choose that option.
Is the comparison case-insensitive?
It can be. Enable case-insensitive matching so Ben@example.com and ben@example.com are treated as the same address.
Does it remove duplicates within a list?
Yes. Duplicates inside a single list are collapsed so they do not distort the in-both or only-in counts.
Can I compare more than emails?
Yes. The list comparator works on any line-separated values, such as IDs, SKUs, or usernames.
Are my lists uploaded?
No. The comparison runs locally in your browser. Neither list is sent to a server.
List comparison runs locally in your browser. Your lists are not uploaded.
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