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 & Identity ControlBuild trust with mailbox providers through SPF, DKIM, and DMARC alignment.
- Infrastructure & Routing StrategiesLearn how your sending IPs, domains, and routing choices impact reputation.
- List Quality & 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 & BlacklistsAvoid the signals that can instantly damage your reputation and inbox rates.
The Human Layer
3 articles- CAN-SPAM, GDPR, & CASLStay compliant with key global email laws that protect user privacy and trust.
- Content Psychology & Filtering SignalsWhy content rarely causes spam placement—and the subtle signals that still matter.
- User Expectations & EngagementHow user behavior shapes reputation far more than content or infrastructure.
Playbooks & 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 & 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.