Gmail address normalizer — collapse aliases back to real inboxes
The Gmail generator does one thing: it turns a single address into a mountain of dot and plus aliases, all of which land in the same inbox. This tool is the exact opposite. Paste a messy list — exports, sign-up logs, whatever — and it works out which addresses are secretly the same Gmail mailbox, strips them back to their real form, and removes the duplicates.
What counts as the "real" Gmail address
Google treats several spellings of one username as a single mailbox. To find the canonical form, apply four rules — in this order — to the part before the @:
JohnSmith → johnsmith+johnsmith+news → johnsmithj.o.h.n.smith → johnsmith@googlemail.com → @gmail.comSo John.Smith+news@gmail.com, j.o.h.n.smith@googlemail.com and JOHNSMITH@gmail.com are all one inbox: johnsmith@gmail.com. That is exactly what the tool above reports.
Which characters Gmail actually allows
This matters, because it is why the rules above are safe. A Gmail username is not free-form — Google only permits:
- Letters
a–z(case is ignored on delivery); - Digits
0–9; - Dots
.— allowed, but ignored, and not permitted at the very start or end, nor two in a row when you register.
Everything else you might see in the local part is not part of the real username:
- A
+introduces a throwaway tag — anything from the+up to the@is a label you invented, not the account. - Characters like
_,-or%are valid in the wider email standard (RFC 5321), but Gmail does not let you register a username containing them. So if you see one, the address is almost certainly not a plain Gmail account — and the tool leaves it alone.
gmail.com and googlemail.com addresses. On those, dots and case genuinely do not matter. On any other domain they might, so touching them could point mail at the wrong person.gmail.com versus googlemail.com
When Gmail launched, trademark disputes in some countries forced the googlemail.com domain instead. The two have always shared the same accounts: mail to you@googlemail.com and you@gmail.com arrives in the identical inbox. For a clean, comparable list, the tool folds googlemail.com into gmail.com so the two spellings do not look like two different people.
Why the trick is not universal
The dot and plus rules are a Gmail convention, not an internet law. Other providers each make their own choice:
- Plus tags are supported by many (Outlook, Fastmail, iCloud, Proton) — but not all, and some strip them on the way out.
- Dots are significant almost everywhere except Gmail:
j.smith@outlook.comandjsmith@outlook.comcan be two different people.
Because guessing wrong would merge two real strangers into one line, this tool is deliberately conservative: outside Gmail it only lower-cases the address and leaves the local part untouched.
Frequently asked questions
Does removing dots change where mail goes?
Not for Gmail. j.o.h.n@gmail.com and john@gmail.com are the same mailbox, so collapsing the dots is safe. For other providers the tool does not remove dots, precisely because there it could change the recipient.
Will it merge two different people by mistake?
Only if they genuinely share one Gmail inbox, which by definition they do not. Non-Gmail domains are never merged on dots or case, so unrelated addresses stay separate.
Is my pasted list sent anywhere?
No. Everything happens in your browser; closing the tab discards it entirely.
How do I go the other way — one address into many aliases?
Use the companion Gmail generator, which expands a single username into every dot and plus variant.