Is Litmus pre-send spam testing sufficient for deliverability monitoring?

Summary

The overwhelming consensus from marketers, experts, and documentation sources is that pre-send spam testing, while useful for identifying immediate issues, is not sufficient for comprehensive email deliverability monitoring. A holistic, multi-faceted approach is required, encompassing both pre-send checks (content analysis, rendering, authentication) and post-send analysis (inbox placement, bounce rates, complaint rates, engagement metrics, sender reputation). Proper authentication (SPF, DKIM, DMARC), diligent list hygiene, and monitoring sender reputation are also critical components of a successful deliverability strategy.

Key findings

  • Pre-Send Inadequacy: Pre-send testing alone is not enough for comprehensive deliverability monitoring.
  • Holistic Approach: A multi-faceted approach combining pre- and post-send monitoring is essential.
  • Authentication Importance: Proper implementation of SPF, DKIM, and DMARC is crucial for sender authentication and deliverability.
  • List Hygiene: Maintaining a clean and engaged email list is vital to avoid spam filters.
  • Sender Reputation: Monitoring sender reputation provides valuable insights into how mailbox providers view your sending practices.
  • Post-Send Engagement: Metrics like inbox placement, bounce rates, complaint rates and engagement rates show how recipients view your emails

Key considerations

  • Integrated Toolset: Utilize both pre-send testing tools and post-send monitoring platforms for complete visibility.
  • Comprehensive Strategy: Combine technical measures (authentication) with list management and performance tracking.
  • Real-World Data: Prioritize analysis of real-world email performance over relying solely on pre-send simulations.
  • Continuous Monitoring: Deliverability is an ongoing process, requiring continuous monitoring and adaptation.

What email marketers say
9Marketer opinions

The consensus is that pre-send spam testing, while valuable for identifying issues like broken links, rendering problems, and spam triggers, is not sufficient for comprehensive deliverability monitoring. A multi-faceted approach is required, incorporating post-send monitoring of inbox placement, engagement metrics (bounce rates, complaint rates), sender reputation, and authentication (SPF, DKIM, DMARC). List hygiene is also crucial.

Key opinions

  • Pre-Send Testing Limitations: Pre-send testing identifies potential issues before sending but doesn't reflect actual inbox placement or user engagement.
  • Post-Send Monitoring Importance: Monitoring inbox placement, bounce rates, complaint rates, and engagement is crucial for a complete deliverability picture.
  • Authentication is Key: Proper implementation of SPF, DKIM, and DMARC protocols is essential for establishing sender legitimacy and improving deliverability.
  • List Hygiene: Maintaining a clean email list by removing hard bounces and inactive subscribers is critical for avoiding spam filters.
  • Sender Reputation: Monitoring sender reputation allows you to see how mailbox providers are viewing your email sending habits

Key considerations

  • Multi-Tool Approach: Employ both pre-send testing tools (like Litmus) and post-send monitoring tools (like MXToolbox or GlockApps) for a comprehensive strategy.
  • Holistic Strategy: Combine technical aspects (authentication) with list management practices and performance monitoring.
  • Proactive vs. Reactive: Pre-send testing is a proactive measure, while post-send monitoring is a reactive measure that allows you to adapt to deliverability issues in real-time.
  • Engagement Metrics: Pay close attention to how recipients are interacting with your emails (opens, clicks, replies) as these signals impact deliverability.
Marketer view

Email marketer from StackExchange suggests using multiple tools. Pre-send checks help identify problems, but post-send checks are important to see if the messages have gone into inboxes or the spam folder.

March 2024 - StackExchange
Marketer view

Email marketer from SendGrid explains that a multi-faceted approach is needed for monitoring email deliverability. This involves using pre-send testing to detect potential deliverability issues before sending, but it also involves ongoing monitoring of metrics like bounce rates, complaint rates, and engagement to gain a comprehensive insight into how your emails are performing.

July 2023 - SendGrid
Marketer view

Email marketer from Neil Patel shares that focusing on list hygiene, proper authentication (SPF, DKIM, DMARC), and monitoring sender reputation are crucial for email deliverability and suggests using tools for both pre-send and post-send analysis.

April 2024 - Neil Patel
Marketer view

Email marketer from Email on Acid suggests that while pre-send testing ensures emails render correctly and avoid spam filters, post-send monitoring of inbox placement and engagement is crucial to assess actual deliverability and make necessary adjustments.

January 2024 - Email on Acid
Marketer view

Email marketer from Reddit shares that a good strategy includes both pre-send testing, to catch obvious errors, and post-send monitoring, to analyze actual inbox placement rates.

June 2021 - Reddit
Marketer view

Marketer from Email Geeks shares that MXToolbox.com has automated monitors, including Delivery Center for SPF, DKIM, DMARC, and BIMI monitoring and management. It dynamically monitors sending IPs and offers managed reputation services, alerting to factors affecting inboxing.

November 2022 - Email Geeks
Marketer view

Email marketer from Gmass explains that list hygiene is essential. You need to remove hard bounces and users who haven't been active in a long time. If you don't do this, your emails may go to spam.

February 2023 - Gmass
Marketer view

Email marketer from GlockApps shares that using a deliverability monitoring tool helps you measure inbox placement rates, identify potential authentication issues, and find out which spam filters are blocking your emails. The deliverability score is also helpful to measure improvements.

April 2021 - GlockApps
Marketer view

Email marketer from Litmus explains that pre-send testing helps identify potential deliverability issues like broken links, rendering problems, and spam trigger words, but it doesn't replace post-send monitoring which tracks actual inbox placement and engagement.

July 2023 - Litmus

What the experts say
2Expert opinions

Experts agree that pre-send spam testing, while helpful, is not sufficient for complete deliverability monitoring. A comprehensive approach is required, integrating post-send analysis of inbox placement, engagement metrics, sender reputation, authentication methods, seed testing, list management, and feedback loops to fully understand the user experience.

Key opinions

  • Pre-Send Testing Insufficiency: Relying solely on pre-send testing provides an incomplete view of deliverability.
  • Holistic Monitoring Needed: Comprehensive monitoring requires a combination of pre-send checks and post-send analysis.
  • Importance of Feedback Loops: Feedback loops and user experience metrics are essential components of effective deliverability monitoring.

Key considerations

  • Integrated Approach: Integrate pre-send testing with post-send monitoring for a complete deliverability strategy.
  • Multi-Faceted Assessment: Consider authentication, list management, and sender reputation in addition to spam triggers and rendering issues.
  • User-Centric Perspective: Focus on the user experience and monitor user engagement to gain insights into deliverability performance.
Expert view

Expert from Spamresource.com explains that relying solely on pre-send testing is insufficient. Monitoring deliverability requires a holistic view including authentication, list management and looking at metrics from seed testing, and post-send feedback loops to understand the user experience.

March 2023 - Spamresource.com
Expert view

Expert from Word to the Wise explains that while pre-send testing helps catch errors and spam triggers, it's not enough for comprehensive monitoring. You need to combine it with post-send monitoring of inbox placement, engagement metrics, and sender reputation to truly understand deliverability.

December 2021 - Word to the Wise

What the documentation says
4Technical articles

Official documentation emphasizes that comprehensive deliverability monitoring requires both pre-send checks (like content analysis and authentication) and post-send analysis (bounce rates, spam complaints, engagement). Monitoring sender reputation via tools like Google Postmaster Tools is crucial. SPF and DMARC are essential for email authentication, preventing spoofing, and enhancing deliverability by verifying sender domains.

Key findings

  • Comprehensive Monitoring: Deliverability monitoring requires pre- and post-send analysis for a holistic view.
  • Sender Reputation: Monitoring sender reputation through tools like Google Postmaster Tools is essential.
  • Authentication Importance: SPF and DMARC records are crucial for email authentication, preventing spoofing, and improving deliverability.

Key considerations

  • Implement Authentication: Properly configure and maintain SPF and DMARC records.
  • Monitor Performance: Track bounce rates, spam complaints, and engagement metrics post-send.
  • Utilize Monitoring Tools: Use tools like Google Postmaster Tools to monitor sender reputation and identify potential deliverability issues.
Technical article

Documentation from RFC explains SPF (Sender Policy Framework) records are essential for email authentication, helping to prevent spoofing and improving deliverability by verifying the sender's domain. SPF records need to be configured correctly and updated to accurately reflect authorized sending sources.

August 2021 - RFC
Technical article

Documentation from Mailjet explains that deliverability monitoring should include both pre-send checks (authentication, content analysis) and post-send analysis (bounce rates, spam complaints, engagement metrics) to get a comprehensive view of email performance.

March 2025 - Mailjet
Technical article

Documentation from Google Postmaster Tools explains that monitoring sender reputation through their tools is essential for understanding how Google perceives your email sending practices, impacting deliverability to Gmail users. It highlights that while pre-send checks are important, real-world performance data is critical.

December 2024 - Google
Technical article

Documentation from DMARC.org explains that DMARC (Domain-based Message Authentication, Reporting & Conformance) builds on SPF and DKIM to provide a policy framework for email authentication. Implementing DMARC allows domain owners to specify how email receivers should handle messages that fail authentication, providing valuable feedback for monitoring and improving deliverability.

April 2021 - DMARC.org