dmarcexpert

Free tool

Free DKIM checker

Look up a DKIM public key at a selector you provide.

The selector is the label chosen when DKIM was set up (it appears as selector._domainkey.yourdomain). There is no way to discover it automatically, so enter the one your provider gave you.

What this checks

  • Whether a DKIM public key exists at the selector you enter.
  • The key type and length, and any warnings.
  • We never guess selectors: there is no way to discover one for a domain you do not control.

Not sure which selector to enter? It is in the headers of any message you send. See how to find your DKIM selector. To see the full picture for a domain, run the DMARC checker.