Free tool

MX Lookup & Email DNS Checker

Check the mail servers, SPF, DKIM, DMARC, MTA-STS and BIMI records of any domain — and see exactly what is hurting your email deliverability.

What this checker looks at

MX records
The mail servers that accept email for the domain, in priority order, with the IP address behind each one.
SPF
A TXT record listing which servers may send mail as your domain. Only one SPF record is allowed, and it should end with ~all or -all.
DKIM
A public key that lets receivers verify the cryptographic signature on your messages. We test the most common provider selectors.
DMARC
Tells inboxes what to do when a message fails SPF and DKIM, and where to send reports. p=none only monitors — move to quarantine or reject.
MTA-STS and BIMI
Optional extras: MTA-STS enforces TLS on inbound mail, BIMI shows your brand logo beside messages in supporting inboxes.

Frequently asked questions

Why is my mail going to spam?
Nine times out of ten it is a missing SPF or DKIM record, or a DMARC policy left at p=none. Fix every failing item above first.
DKIM shows no key — is that a problem?
Not necessarily. DKIM selectors are chosen by your provider, so a custom selector we do not test may still exist. Check your provider's DNS instructions.
I just changed a record.
Resolvers cache answers for the record's TTL. Use the DNS propagation checker to see how far the change has travelled.

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