Email Authentication: Setting Up DKIM, SPF, and DMARC

Why Email Authentication Matters

Without proper email authentication, your legitimate emails look like spam to Gmail, Outlook, and other providers. SPF, DKIM, and DMARC work together to prove you are who you say you are.

SPF (Sender Policy Framework)

SPF is a DNS TXT record that lists which mail servers are allowed to send email for your domain.

v=spf1 include:mail.hostinking.com ~all

DKIM (DomainKeys Identified Mail)

DKIM adds a cryptographic signature to every outgoing email. The recipient's mail server checks this signature against a public key in your DNS. If the signature matches, the email is genuine.

DMARC

DMARC tells receiving servers what to do when an email fails SPF or DKIM checks — either quarantine it, reject it, or do nothing.

v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com