Email Normalizer
Canonicalize any email address to its deliverable form — lowercase, strip Gmail dots and +tag sub-addresses, fold googlemail.com to gmail.com. Runs entirely in your browser, no server, no sign-up.
What this tool does
The Email Normalizer turns an email address into its canonical form — the single deliverable address that a mailbox actually receives, with cosmetic and provider-specific variations removed. It runs entirely in your browser: nothing is sent to a server, it works offline, and there is no sign-up.
Paste an address (a Name <addr> or mailto:addr wrapper is unwrapped
automatically) and it reports the canonical address plus what was changed.
What gets normalized
| Step | What happens |
|---|---|
| Lowercase the domain | DNS is case-insensitive, so Example.COM becomes example.com. |
| Lowercase the local part | On by default — virtually every provider treats the part before @ case-insensitively. Turn it off to keep the original case. |
Strip the +tag sub-address | you+newsletter@… and you+shopping@… both deliver to you@…, so the tag is removed (and reported). |
| Remove Gmail dots | Gmail ignores . in the local part, so [email protected] is the same mailbox as [email protected]. Dots are removed for Gmail only. |
Fold googlemail.com | Google's old domain googlemail.com is folded to gmail.com. |
Provider rules
Dot-stripping applies to Gmail / Googlemail only. Sub-address (+tag)
removal applies to every recognized provider — Gmail, Outlook / Hotmail /
Live, Yahoo, iCloud, Fastmail, and Proton Mail — and to any other domain, since
plus addressing is the de-facto standard. Other providers keep their dots.
Examples
| Input | Output (canonical) |
|---|---|
[email protected] | [email protected] |
[email protected] | [email protected] |
[email protected] | [email protected] |
Jane Roe <mailto:[email protected]> | [email protected] |
[email protected] | [email protected] |
Why normalize email addresses?
- Deduplicate sign-ups —
[email protected]and[email protected]are the same person; comparing canonical forms catches duplicate accounts and abuse. - Match records — reconcile a contact list where the same mailbox was typed several different ways.
- Validate input — the tool flags syntactically invalid addresses (missing
@, no domain dot, bad characters) so you can catch typos.
FAQ
Is it free and private?
Yes — your input never leaves your device, and it keeps working offline once the page has loaded.
Does removing dots affect non-Gmail addresses?
No. Only Gmail ignores dots in the local part, so dots are preserved for every other provider.
What about the +tag part — is that mail lost?
No. A message to
you+anything@… is delivered to you@…; the tag is just a filtering label, so
the canonical address still reaches the same inbox.
Can I keep the local part's capitalization?
Yes — untick Lowercase the local part. The domain is always lowercased because DNS is case-insensitive.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool email-normalizer "[email protected]"New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/email-normalizer/?email=John.Doe%2Bnewsletter%40googlemail.com&lowercase_local=trueMachine-readable descriptor: tool.json — title + parameters JSON Schema for agents.