DKIM Checker
Look up selector._domainkey TXT public keys.
DKIM publishes a public key in DNS so receivers can verify message signatures. You must know the selector used by your ESP or mail platform (for example google, s1, or a custom name). DNS Checkers queries selector._domainkey.domain and checks for DKIM-looking TXT content. Rotate keys carefully and keep DMARC alignment in mind. Related: SPF, DMARC, header analyzer.
Frequently asked questions
Quick answers about propagation, resolvers, and how this checker works.
Are email auth results a guarantee of inboxing? +
No. They show published DNS policy and banners. Inbox placement also depends on reputation and content.
Does DNS Checkers send email during SMTP tests? +
No. SMTP tests only connect and read a banner, then quit.
Where do SPF/DKIM/DMARC live? +
SPF and DKIM publish in TXT; DMARC lives at _dmarc.domain as TXT.
Is this free? +
Yes. Phase 2 email tools are free with the same AdSense-safe policies as Phase 1.
Can results differ by resolver? +
Yes. After DNS edits, use the propagation checker while caches expire.