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 bilibili.com

Found
Selector: selector1 (TXT on selector1._domainkey.bilibili.com)
v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCmOczP4xmlIvJpStrdDBishGdBnEkFKCzefUV99sQb9/6q/KXxWrPjLOjioluDlH/W7V7YotJWWDX3FSJ6nPkOaXOJMI3CB7JJGz3JQhy7YlnGNOxqlt3rRfGAXIsNPgNWoDXFeCXYCRG3qK5Sm7x3w+BL1IP8NhSX7GreMEpOBQIDAQAB;
Selector: selector2 (TXT on selector2._domainkey.bilibili.com)
v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDm584oGtraA39oDvhvK0KZ9TLBh0XqmY7rITuA0OCNg0omB01QjgYYmYUmz8vTVFZMvqnVkBzl29DhMQN7Bp1ck7ti0/8UX3oOSjBz8CWeGlC9FY5xpbsL7Q/GHRa3Z+GKurtyHalQMP/uTR7gs+I/zm8JSJ5CjaQWS5bk0DSLoQIDAQAB;

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.