Free email tool
DKIM selector checker.
Inspect the public DKIM key for a selector your sending service uses.
What this check can tell you
Supply the selector from a signed message to inspect its TXT record and key evidence. Leaving it blank only probes common selector names.
Limit: Common-selector probing is discovery-only. A probe miss does not prove that your domain has no DKIM record or that a live message failed DKIM.