DKIM Checker
Looks up a DKIM public-key record. You need to know the selector (check the sending platform's setup docs, or a "DKIM-Signature" header's s= value).
Frequently asked questions
What is DKIM, and what does the selector mean?
DKIM (DomainKeys Identified Mail) lets a domain cryptographically sign its outgoing mail. The signature is published as a DNS record at selector._domainkey.yourdomain.com — the selector is just a name chosen by whoever set up DKIM (often something like google, s1, or a date). You can usually find it in your email platform's DKIM setup instructions, or in the s= field of a DKIM-Signature header on a received email.
Is this free to use?
Yes, completely free, with no signup or account required.
Do you store the domains or selectors I check?
No. Each check is a live, one-time DNS lookup — we don't save what you type in.