ScanTower

ScanTower is a more advanced email security validator that checks the full stack of email authentication and encryption standards, not just the basics. Beyond SPF, DKIM, and DMARC, it validates MTA-STS (enforcing encrypted connections) and TLS-RPT (reporting when encryption fails), plus BIMI and other emerging standards. It presents results in a clear, color-coded dashboard so you can quickly see what's working and what needs attention.

It's built for larger organizations or security-conscious teams that want comprehensive coverage of email infrastructure. If you're operating at scale and need to audit your sending domains against current best practices, ScanTower gives you a detailed breakdown of your posture across all the standards that matter to mailbox providers. The tool also helps you prioritize improvements since not all configurations are equally urgent for deliverability.