Email Deliverability Testing
Summary
Email deliverability testing validates DNS authentication (SPF, DKIM, DMARC), checks blacklist status, verifies MX records, and measures inbox placement rates. Automated testing through APIs enables continuous monitoring and prevents reputation degradation.
What Is Email Deliverability Testing?
Email deliverability testing is the process of verifying your email infrastructure can successfully deliver messages to recipient inboxes. It combines DNS validation, authentication checks, reputation monitoring, and actual inbox placement testing. IntoDNS provides automated deliverability testing through API endpoints, enabling CI/CD integration and continuous monitoring.
Why Email Deliverability Testing Matters for Email & DNS Security
Deliverability issues are often invisible until critical emails fail. Password resets go undelivered, invoices never arrive, and marketing campaigns waste budget. According to IntoDNS analysis, domains that test deliverability weekly detect authentication issues 12 days faster on average than those testing monthly. Regular testing catches problems before users complain and prevents gradual reputation decay.
How Email Deliverability Testing Works (Technical)
- 1.DNS validation: Check SPF, DKIM, DMARC records exist and are valid
- 2.Authentication testing: Send test emails and verify headers
- 3.Blacklist monitoring: Check sending IPs against RBL databases
- 4.MX record validation: Ensure mail servers are configured correctly
- 5.Inbox placement: Send to seed accounts and check spam vs inbox
- 6.Engagement tracking: Monitor open rates, bounces, and complaints
- 7.Score calculation: Combine metrics into deliverability grade
Common Misconfigurations
❌ Testing only once at setup
Consequence: Miss gradual reputation decay or authentication expiry
How IntoDNS detects this: IntoDNS recommends automated daily testing via API
❌ Ignoring bounce rates
Consequence: High bounce rates damage sender reputation quickly
How IntoDNS detects this: IntoDNS email security check includes MX validation
❌ No blacklist monitoring
Consequence: Discover blacklisting only after deliverability fails
How IntoDNS detects this: IntoDNS checks 15+ major blacklists in every scan
How IntoDNS.ai Detects & Scores This
IntoDNS deliverability testing includes DNS authentication validation (40% of score), security extensions (20%), reputation factors like blacklist status (25%), and technical hygiene including MX records and IPv6 (15%). API enables CI/CD integration.
How To Fix Email Deliverability Testing Issues
- 1.Use IntoDNS API for automated daily scanning
- 2.Integrate into CI/CD: fail builds if score drops below 80
- 3.Monitor DMARC aggregate reports weekly
- 4.Check blacklist status after any infrastructure changes
- 5.Send test emails to seed accounts monthly
- 6.Track bounce rates and remove invalid addresses
- 7.Set up alerts for authentication failures
References
Source: IntoDNS.ai – DNS & email security diagnostics
Last updated: 2026-01-14
Category: deliverability