Deliverability manual
How inbox placement works, what you control, and what to do when it goes wrong.
Foundations
4 articles- Understanding email deliverabilityLearn what email deliverability really means and why it’s different from simple email delivery.
- Signal flowSee how signals move between senders, receivers, and mailbox providers to shape inbox decisions.
- Value chainUnderstand the key players in email and how each one influences deliverability outcomes.
- The signal gameExplore how mailbox providers score emails using history, reputation, and engagement patterns.
Controllables
4 articles- Authentication and identity controlBuild trust with mailbox providers through SPF, DKIM, and DMARC alignment.
- Infrastructure and routing strategiesLearn how your sending IPs, domains, and routing choices impact reputation.
- List quality and acquisition integrityWhy a clean, engaged list matters more than anything else for long-term inboxing.
- Engagement economicsUnderstand how opens, clicks, and complaints drive inbox placement decisions.
The reputation engine
3 articles- Understanding mailbox provider algorithmsPeek into how Gmail, Outlook, and others score your emails behind the scenes.
- How senders earn long-term inboxingMove from unknown sender to trusted sender with consistent, positive signals.
- Red flags: spam traps, complaints and blacklistsAvoid the signals that can instantly damage your reputation and inbox rates.
The human layer
3 articles- CAN-SPAM, GDPR and CASLStay compliant with key global email laws that protect user privacy and trust.
- Content psychology and filtering signalsWhy content rarely causes spam placement—and the subtle signals that still matter.
- User expectations and engagementHow user behavior shapes reputation far more than content or infrastructure.
Playbooks and diagnostics
8 articles- Inbox placement testingLearn practical ways to test and monitor where your emails actually land.
- Analyzing SMTP logsDecode SMTP logs to spot delivery issues before they become major problems.
- Incident: soft bouncesUnderstand why soft bounces happen and how to respond effectively.
- Incident: block bouncesLearn to diagnose and resolve hard blocks that stop mail at the gate.
- Incident: reputation tanking overnightSteps to take when your sender reputation suddenly collapses.
- Google Postmaster Tool: access controlManage access to Google Postmaster Tools for better visibility into Gmail deliverability.
- When to reach postmasterKnow when and how to contact mailbox providers for help with delivery issues.
- Scaling without breaking deliverabilityScale your email volume safely without triggering reputation penalties.
Advanced strategies
3 articles- Domain strategy for complex sendersLearn how to manage multiple domains and subdomains for optimal deliverability.
- Traffic shapingControl sending speed and patterns to stay within mailbox provider thresholds.
- Deliverability as a business leverTurn strong deliverability into a measurable business advantage.
Future of email deliverability
3 articles- AI filters and user-level trustExplore how AI filters and per-user trust models are reshaping inbox placement.
- AI and deliverabilitySee how AI-driven tools will transform email deliverability practices.
- Beyond deliverability opsImagine what email operations look like in a world beyond traditional deliverability.