What is a DKIM Checker?
DKIM cryptographically signs your outgoing email; receivers verify the signature against a public key published in your DNS at selector._domainkey.yourdomain. A missing or empty key means failed verification and worse deliverability.
Enter your domain and the selector from your mail provider’s settings — this checker fetches the record live and verifies a public key is present.
How to use the DKIM Checker
- Enter your domain.
- Enter the selector from your provider (Google Workspace: google; Microsoft 365: selector1/selector2).
- Check the verdict and record.
Frequently asked questions
Where do I find my selector?
In your mail provider’s DKIM settings — or in any email’s headers: the s= tag inside DKIM-Signature is the selector.
Common selectors to try?
default, google (Workspace), selector1/selector2 (Microsoft 365), k1 (Mailchimp), s1/s2 (SendGrid), zoho.
The record exists but p= is empty — what does that mean?
The key was revoked or misconfigured. Generate a fresh key at your provider and update the DNS record.
Does DKIM alone secure my email?
It pairs with SPF, and DMARC ties both to your visible From address. Run the DMARC checker for the full picture.