Email Normalizer
Canonicalize email addresses — strip Gmail dots and +tags, fold googlemail to gmail, and collapse duplicate contacts — 100% in your browser, no upload
🔒 Normalized in your browser — no address is uploaded.
What email canonicalization does
Many different-looking addresses reach the same inbox. Gmail ignores every dot in the local part and anything after a +, so John.Doe+news@gmail.com, johndoe@gmail.com and j.o.h.n.doe@googlemail.com all deliver to one mailbox. This tool rewrites each address to its canonical form — lowercased, with dots and tags removed where the provider ignores them and googlemail.com folded to gmail.com — then collapses the duplicates so a list of addresses becomes a clean set of real, distinct inboxes.
Which providers are handled
Dot-stripping applies only to Gmail and googlemail, the only major provider that ignores dots. Sub-address tags are stripped for the providers that support them: Gmail, Outlook/Hotmail/Live, Yahoo (which uses a - separator instead of +), Fastmail and Proton. Unknown domains are only lowercased, because dot and tag behavior there cannot be assumed. Toggle either transform off to keep dots or tags, and everything runs locally in your browser — paste a mailing list to dedupe it without sending a single address anywhere.
Frequently asked questions
Why do Gmail dots and +tags not matter?
Google ignores every dot in the part before the @ and treats anything after a + as a label, so john.doe@gmail.com, johndoe@gmail.com and johndoe+promo@gmail.com are all the same mailbox. Canonicalizing removes the dots and the tag so those variants match.
Does it strip tags for every provider?
Only for providers that actually support sub-addressing: Gmail, Outlook/Hotmail/Live, Yahoo (which uses a dash, base-keyword@yahoo.com), Fastmail and Proton. Unknown domains are only lowercased, since dot and tag rules differ per host and stripping them could change the real recipient.
Are the email addresses uploaded?
No. All normalization happens in your browser with JavaScript. Your addresses are never sent, stored, or uploaded, so even a private contact list stays on your device.