Email Address Validator
Validate email addresses in bulk against practical RFC 5322 rules, catch typos like gmial.com, and optionally check the domain's MX records over DNS.
Up to 500 addresses are checked instantly in your browser.
john.doe@example.comjane@gmial.combad..dots@example.comWhat is Email Validator?
This email validator checks up to 500 addresses for correct syntax and explains every problem it finds: missing @, invalid characters, dots in the wrong place, too-long parts or an invalid domain. It suggests corrections for common typos in popular domains and, on request, looks up each domain's MX records to see whether it can receive mail.
How to use Email Validator
- Paste email addresses, one per line.
- Optionally allow international (Unicode) addresses.
- Read the verdict and reasons for each address and any "Did you mean" suggestion.
- Press Check MX records to query the mail servers of the valid domains.
Example
john.doe@example.com jane@gmial.com bad..dots@example.com
2 of 3 addresses have a valid format. jane@gmial.com → Did you mean jane@gmail.com? bad..dots@example.com → invalid: two dots in a row.
When to use Email Validator
Use it to clean a mailing list, test form validation rules or understand why an address is rejected. No tool can confirm that a specific mailbox exists without sending an email (SMTP probing is unreliable and often blocked), so treat "valid" as "well-formed with a working mail domain".
How Email Validator works
Syntax rules follow the practical subset of RFC 5321/5322 that mail servers accept: a dot-atom or quoted local part of at most 64 bytes, a domain of LDH labels (1–63 characters, no leading/trailing hyphen), an alphabetic TLD and a total length of at most 254. Typos are found with Levenshtein distance against popular mail domains plus a table of TLD slips (.con → .com). The MX check sends only the domain to Cloudflare DNS-over-HTTPS and recognises null MX records (RFC 7505).
Common Use Cases
- Clean a CSV export before importing it into a newsletter tool.
- Catch typos like jane@gmial.com in sign-up data.
- Check that a company domain has MX records before emailing it.
- Test edge cases (quoted local parts, IP literals) for your own validator.
FAQs
Why is "user@localhost" invalid here?
Real internet mail needs a domain with a TLD. Addresses without a dot in the domain only work inside special local setups.
Are quoted addresses like "john doe"@example.com valid?
Yes per RFC 5322, and the tool accepts them, but it warns because many services reject them.
Is my list uploaded?
No. Syntax checks run in your browser; the optional MX check sends only the domain names to Cloudflare DNS.