Email Validator: Format & Domain Checks
Check an email address for common format errors and optionally inspect its public mail-domain DNS. No verification email is sent.
Check an email address
Understand the checks
Domain classification uses a downloaded community list, not a live mailbox probe. A listed disposable domain is not evidence of abuse; absence from the list does not prove permanence. Free-provider and role-name checks use limited local reference lists.
Disposable-domain data: disposable-email-domains, snapshot 14 September 2026. Community classifications can be incomplete or outdated.
1. Common format
We check the @ separator, mailbox length, dots and public-domain structure. International domains are normalised for DNS. Quoted and international mailbox names are outside this basic checker’s scope.
2. Optional mail route
An MX record indicates where a domain routes email. A Null MX says it accepts no mail. When MX is absent, address records may provide an SMTP fallback.
3. Clear limitations
No SMTP login, recipient probing, test message or account lookup happens. A DNS timeout produces an unknown result, not a claim that an address is invalid.
When email validation helps
Use this as an initial check when a contact address looks misspelled or a verification message has not arrived. Compare the address with what the owner supplied; the tool cannot tell whether a name such as “johm” was intended to be “john”.
Do not treat a free email provider, a role address such as support@, or a temporary address as automatic evidence of fraud. Match the address type to your use case and obtain consent before sending messages.
Domain records can change and cached DNS can lag behind. A result is an observation at the time of the check, not a permanent deliverability certificate.
References: Google Public DNS API and Null MX specification (RFC 7505).
Frequently asked questions
Can this confirm that an email address exists?
No. It checks common syntax and, optionally, public DNS. Only a successful ownership-verification workflow can confirm that someone controls an address.
Will this send a message to the address?
No. It does not send mail or probe the recipient’s mail server.
What does “MX records found” mean?
The domain advertises a mail route. It does not confirm that the particular inbox exists, has space, or will accept your sender.
Why is DNS unavailable?
A network problem, provider limit or DNS failure can prevent a lookup. Retry later. An unavailable check must not be read as a valid or invalid result.
Can I check an international email address?
International domain names are supported through their DNS representation. International or quoted mailbox names before @ are outside this checker’s scope and are not automatically invalid.
Can I validate a bulk mailing list here?
No. This is a single-address troubleshooting tool, not a bulk recipient-enumeration service.