DKIM Record Checker
DKIM signs outgoing emails. Receivers verify the signature using a public key in DNS.
DKIM lives on <selector>._domainkey.<domain>. If selector is empty, we try common ones.
Result for 100host.biz
Found
Selector: default
(TXT on default._domainkey.100host.biz)
v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEApMTq3nRT71QlHzme96khJKO7wbK9Gf2hyORwqvFeXQzKnxHZbX2YiQz0CRzXJQ80EAiNnCN1q+6s4WEYg7gssfW/YCDNZzUdHesgmaGJ3cBpCSCc3kMbyPvkCvt12PZLrx/F2epgXXxj0W9TKP1tnULT4MVRffs61lDf/i5rUEJpFCHaZ6MEkxBAQ0Sy4zAkcqgbKL38XVOIpoHcdLLeqUE/loBnrDVTgv79bDxH5ot0tbNCMZ35Q8kSJNW6r21Pw3frok84tHfas5boLgrr6pG122Oi5KLBuBPLje1q1v51VDGxWs9sVTzvCQsuYnm/IPTETTNN8hmKjdabudXKCwIDAQAB;
FAQ
Why does DKIM require a selector?
Selectors allow rotating keys and running multiple keys per domain.
Where is DKIM published?
TXT on <selector>._domainkey.<domain>.
DKIM record exists but emails still fail DKIM?
Signing may be disabled or the selector used in email differs from DNS.
Do I need DKIM if I have SPF?
Yes, many providers use both for best deliverability and DMARC alignment.
Can I have multiple DKIM selectors?
Yes, that is common for key rotation or multiple senders.
What is DKIM?
DKIM (DomainKeys Identified Mail) adds a cryptographic signature to outgoing emails. DNS stores a public key that allows receivers to verify authenticity.
Example
v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0B...
Common mistakes
- Wrong selector (the record exists but under a different selector).
- Key is split incorrectly across multiple TXT chunks (some DNS UIs break it).
- Publishing DKIM but not enabling signing on the mail provider.