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Free Email Address Validator — Real-Time SMTP Check

Syntax, DNS/MX, SMTP probe, catch-all, disposable, role-based and typo suggestions — in one sub-second request. 20 verifications/min free. No signup.

Enter an email to verify:

How it works

1️⃣

Syntax & DNS

RFC-5321 syntax, MX lookup with A/AAAA fallback, retry on tempfail.

2️⃣

SMTP probe

EHLO/MAIL FROM/RCPT TO against the primary MX with MX fallback & deadline.

3️⃣

Grade & verdict

Composite 0-100 score, A–F grade, catch-all and role-based flags, typo suggestion.

What each status means

StatusMeaningWhat to do
validInbox exists, mail will accept.Send safely.
riskyCatch-all / role-based / suspicious pattern.Send but monitor bounces.
invalidMailbox rejected, disposable, or bad syntax.Remove from list.
unknownGreylisted / temp fail.Retry in 15 min.

Examples

  • test@gmial.cominvalid · suggestion: test@gmail.com
  • admin@somecompany.comrisky · role-based
  • junk@mailinator.cominvalid · disposable
  • xqzabc998877@example.comrisky · likely random local
  • sundar@google.comrisky · catch-all domain

Frequently asked questions

Is it really free?

Yes. 20 free checks/minute/IP, no signup. Paid plans raise the limit and add batch cleaning.

How accurate is the SMTP probe?

~98% for normal domains. Catch-all domains always accept, so we flag them as risky rather than valid.

What is a deliverability score?

A composite of syntax, DNS, SMTP, catch-all, role-based, disposable and MX-health checks — mapped to a letter grade A–F.

Will my emails be stored?

No. The single validator is stateless. For paid batch cleaning, files are processed in memory and deleted within 24h.

How do typo suggestions work?

We compare the domain to a list of ~60 common providers using Levenshtein distance. gmial.comgmail.com.

Can I use the API?

Yes. POST /api/validate-email. Grab an API key from your dashboard for raised limits.

What languages / frameworks?

Any HTTP client: cURL, fetch, requests, axios, Guzzle. See API docs.

Need higher volume?

Pro plan at $0.001/email covers 50,000+/month.

Verify thousands at once?

Try Bulk Cleaner →