Mail Hub checks common mail-authentication and routing signals for connected domains.
- MX: identifies where inbound mail is routed.
- SPF: identifies systems authorized to send for the domain.
- DKIM: provides cryptographic message signing through the sending provider.
- DMARC: defines domain policy and reporting for SPF/DKIM alignment.
A healthy DNS score does not guarantee inbox placement. Reputation, volume, recipient engagement, message content and provider policy also matter.