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DKIM Record Checker

A DKIM key lets your mail server cryptographically sign outgoing email so receivers can verify it wasn't altered. Keys live under a selector (e.g. google._domainkey). This checker probes the most common selectors automatically, if yours is custom it may exist even when not shown here.

DKIM Checker, FAQ

What is DKIM?
DKIM (DomainKeys Identified Mail) adds a cryptographic signature to your emails using a private key; the matching public key is published in DNS under a selector so receivers can verify the message.
Why can't you always find a DKIM record?
DKIM keys are stored under a selector name chosen by your provider. There is no way to list selectors from DNS, so a checker must guess common ones. A missing result here doesn't always mean DKIM is absent.
How do I find my DKIM selector?
Look at the DKIM-Signature header of an email you sent (the s= tag), or check your email provider's DNS setup instructions.

Want the complete picture? The Deliverability Radar scores a domain or IP out of 100 across DNS, authentication, reputation and connectivity, and emails you a branded PDF.

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