Free tools to check your domain's DNS, SPF, DKIM and DMARC, and your mail server's reputation on blacklists.
A domain opens the SPF check, an IP address opens the blacklist check.
Check which servers may send email for your domain and whether the record stays under the 10-lookup limit.
Look up and verify a DKIM public key - or let us find your selector.
Check your DMARC policy, alignment and where reports are sent.
Paste the headers of a received email to see authentication results, alignment and delays.
Send a test email to us and see how a real mail server judges it.
Is your mail server's IP on Spamhaus, Barracuda, SpamCop or other blacklists?
Get a regular email report about your IP addresses on blacklists.
Check the PTR record of your mail server and that it resolves back to the same IP.
A, AAAA, CNAME, MX, TXT, NS, SOA and CAA records via the resolver of your choice.
Which mail, web and remote-access ports of your server are reachable from the internet?
Your public IP address, location and network provider.
Measure download, upload, ping and jitter.
DNSMailSecure.com v3.0.0
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