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  3. DKIM checker
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DKIM checker

Look up the DKIM TXT record for a domain and selector and read back its tags, public key and settings in plain terms.

This tool is in beta

Still being tested. If a result looks wrong, tell us.

Report a problem

Type a domain and a selector, then press Check DKIM

The tool looks up the TXT record at selector._domainkey.domain and reads its tags, public key, and settings back in plain terms.

A DKIM selector cannot be listed out of DNS; the mail operator picks it, so this tool resolves exactly one name per run. Finding a record proves it is published, not that it is correct: the tool does not verify RSA or Ed25519 signatures, does not match the key against a received mail header, and an empty p= is reported as revoked rather than guessed around.

Selector lookup

Up to 253 characters
Chosen by whoever configured DKIM; it cannot be discovered from DNS
Common selectorsOne tap to try
Resolver

What leaves your browser

One DNS-over-HTTPS TXT query for selector._domainkey.domain goes to the selected resolver over HTTPS and nowhere else. This page leaves your browser only when you press the button; never on load, never in the background. Nothing is sent anywhere else. Google Analytics still measures the visit to this page, and it never receives what you run through this tool.

More network tools

  • Live DNS lookup
  • DNS explainer
All network tools

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