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Q & A Email Auth · August 5, 2026

What is a DKIM selector?

A selector is a label you choose that forms the first part of the DKIM DNS record name: selector._domainkey.yourdomain.com. It lets you publish multiple DKIM keys (one per sending service) without conflict. The selector is embedded in every outgoing email’s DKIM-Signature header so receiving servers know which DNS record to look up.

Read the full guide
What Is DKIM? How DomainKeys Identified Mail Works
DKIM attaches a cryptographic signature to every email you send. Receiving servers verify the signature against a public key in your DNS — proving the message is authentic and untampered. No DKIM means anyone can forge your brand's email.
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