DKIM Record Inspector & Validator.
Inspect public RSA cryptographic keys, test key-length compliance (2048-bit vs deprecated 1024-bit), and verify selector DNS alignment.
What this inspector evaluates:
DKIM proves that outgoing emails were not altered between your server and the recipient's mailbox:
p=...).Understanding DKIM Signatures & Selectors.
DKIM signatures allow mailbox providers to cryptographically verify the authenticity of email senders. Learn how selectors function in DNS.
What is a DKIM Selector?
A selector is a string identifier assigned by your mail service that points to a specific public key in your DNS at [selector]._domainkey.yourdomain.com. It allows different email streams (Google, SendGrid, Amazon SES) to publish their own keys under the same domain.
Why is 2048-bit RSA key length recommended over 1024-bit?
1024-bit RSA keys are now considered computationally weak and can theoretically be factored by modern cloud compute clusters. Major mailbox providers like Google, Yahoo, and Microsoft strongly advise all domains to upgrade to 2048-bit keys.
Where do I locate my domain's DKIM selector?
In Google Workspace, the selector is usually google. In Microsoft 365, it is selector1. In transactional providers like SendGrid or Mailgun, look inside your Domain Authentication dashboard settings.
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