Question 1

What is DKIM and what does a selector do?

Accepted Answer

DKIM (DomainKeys Identified Mail) lets a sending mail server cryptographically sign outgoing email so receivers can verify it wasn't altered in transit. The selector is a short label, chosen by your email provider, that points to the specific public key published in DNS — it's why DKIM records live at selector._domainkey.yourdomain.com rather than just _domainkey.yourdomain.com.

Question 2

Where do I find my DKIM selector?

Accepted Answer

Your email or marketing platform's DNS setup instructions will specify it — common examples include "google" for Google Workspace, "selector1"/"selector2" for Microsoft 365, or a custom value for services like Mailchimp or SendGrid. Check your provider's documentation if you're unsure.

Question 3

I get no result — does that mean DKIM isn't set up?

Accepted Answer

It usually means either DKIM signing hasn't been enabled with your provider yet, the DNS record hasn't been added, or you've entered the wrong selector. Double-check the exact selector value in your provider's dashboard and confirm the DNS record was saved.

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