Summary
The best seed testing companies for email marketing encompass a range of options, including Kickbox, GlockApps, MailMonitor, and Validity (Everest). Sparkpost's Inbox Tracker also offers seed testing capabilities. These tools facilitate the monitoring of email deliverability across various ISPs by sending test emails to a seed list. While some experts recommend these paid services, others suggest supplementing them with free tools like Mail-Tester or creating custom seed lists for more targeted insights. It's consistently emphasized that seed testing alone is insufficient for a comprehensive deliverability strategy and should be combined with other methods, such as feedback loops, authentication, reputation monitoring, and inbox placement tests, to gain a holistic view of email performance.
Key findings
- Top Recommended Tools: GlockApps, MailMonitor, Kickbox, and Validity (Everest) are frequently cited as effective seed testing tools.
- Inbox Tracker Alternative: Sparkpost's Inbox Tracker provides seed testing capabilities and can be used by senders regardless of their ESP.
- DIY and Free Options: Creating custom seed lists and using free tools like Mail-Tester can supplement paid services.
- Comprehensive Testing: Seed testing should be part of a larger deliverability strategy including authentication and reputation.
Key considerations
- Limited Scope: Seed testing provides a limited snapshot of deliverability and may not accurately reflect real-world results due to filtering and personalization.
- Integrated Approach: Combine seed testing with other deliverability techniques for a more complete assessment of email performance.
- Budget & Feature Considerations: Choose a seed testing solution that aligns with your budget and offers features relevant to your specific needs.
What email marketers say
13 marketer opinions
The best seed testing companies for email marketing, as identified across various platforms, include GlockApps, MailMonitor, and Validity (Everest, formerly 250ok and Return Path). Sparkpost's Inbox Tracker is also a viable option. These services help monitor deliverability by sending test emails to seed lists and analyzing inbox placement. Some users supplement paid services with free tools like Mail-Tester or create their own seed lists for targeted insights. It's also noted that seed testing alone is insufficient and should be combined with other deliverability techniques like feedback loops, authentication, reputation monitoring, and inbox placement tests for a comprehensive deliverability strategy.
Key opinions
- Top Tools: GlockApps, MailMonitor, and Validity (Everest) are consistently recommended seed testing companies.
- Inbox Tracker: Sparkpost's Inbox Tracker enables senders using any ESP to monitor deliverability.
- DIY Seed Lists: Creating a manual seed list is an option for smaller campaigns to provide direct insights.
- Free Tools: Mail-Tester is a suggested free tool to use alongside paid seed testing services.
Key considerations
- Comprehensive Approach: Seed testing should be part of a broader deliverability strategy, including feedback loops, authentication, and reputation monitoring.
- Limitations: Seed testing provides a limited snapshot and doesn't reflect real-world results from personalized filtering.
- Tool Choice: Consider individual requirements when selecting a seed testing company based on budget, coverage, and features.
Marketer view
Email marketer from EmailToolTester.com explains that seed list testing involves sending your email to a list of seed email addresses across various mailbox providers to check where your email lands (inbox, spam, or missing). They recommend GlockApps, MailMonitor, and 250ok (Validity)
5 Dec 2022 - EmailToolTester.com
Marketer view
Email marketer from Reddit explains that using a combination of seed testing tools and feedback loops is ideal. They suggest GlockApps for seed testing and mention Return Path (now Validity) for reputation monitoring.
1 Apr 2022 - Reddit
What the experts say
4 expert opinions
Experts recommend various seed testing companies for email marketing, including Kickbox, Email Consul, Glockapps, Inboxable, Inbox Monster, Mail Monitor, Postmastery, and Validity. Kickbox offers a range of services beyond seed testing, such as blocklist monitoring, DMARC, and spam/render testing. However, seed testing provides a limited snapshot of deliverability and should be combined with other methods like authentication and reputation monitoring for a comprehensive assessment.
Key opinions
- Recommended Tools: Kickbox, Email Consul, Glockapps, Inboxable, Inbox Monster, Mail Monitor, Postmastery, and Validity are mentioned as seed testing options.
- Kickbox Features: Kickbox provides seedlist testing, blocklist monitoring, DMARC services, and spam/render pre-checks.
- Limited View: Seed testing offers a limited view of deliverability and may not reflect real-world results.
Key considerations
- Comprehensive Testing: Seed testing should be used with other methods like authentication and reputation monitoring for a comprehensive deliverability assessment.
- Tool Features: Consider the range of features offered by each company beyond just seed testing (e.g., blocklist monitoring, DMARC services).
- Real-World Results: Be aware that seed testing results may not perfectly reflect deliverability to actual subscribers due to filtering and personalization.
Expert view
Expert from Email Geeks shares a list of seed testing companies including Email Consul, Glockapps, Inboxable, Inbox Monster, Kickbox, Mail Monitor, Postmastery and Validity for all budgets.
8 Sep 2022 - Email Geeks
Expert view
Expert from Word to the Wise shares that while seed testing is one component, it should be used in conjunction with other deliverability testing methods for a comprehensive picture of your email program's performance. They mention factors like authentication and reputation monitoring as crucial elements.
14 Jan 2023 - Word to the Wise
What the documentation says
4 technical articles
Seed list testing, as explained by SendGrid, Mailjet, GlockApps, and SparkPost, involves sending test emails to a controlled list of email addresses at various ISPs to monitor placement. This method helps identify and address potential deliverability issues before sending to a large subscriber list. GlockApps and SparkPost (Inbox Tracker) offer platforms that facilitate this process, enabling users to analyze deliverability across different ISPs.
Key findings
- Early Issue Detection: Seed list testing helps catch deliverability problems before widespread distribution.
- ISP Monitoring: The method monitors email placement across various Internet Service Providers (ISPs).
- Platform Support: GlockApps and SparkPost's Inbox Tracker offer platforms that support seed list monitoring and analysis.
Key considerations
- Controlled Environment: Seed lists provide a controlled environment for assessing deliverability.
- Pre-Campaign Use: Seed testing is most effective when conducted before sending a large-scale email campaign.
- Deliverability Analysis: The focus is on analyzing deliverability metrics across different ISPs to identify potential problems.
Technical article
Documentation from GlockApps explains that their platform offers seed list monitoring, allowing users to send test emails to their seed list and analyze deliverability across various ISPs. This helps in identifying and addressing deliverability issues before a large-scale campaign.
20 Dec 2021 - GlockApps.com
Technical article
Documentation from Mailjet explains that seed list testing is a method to monitor email deliverability by sending test emails to a list of seed email addresses at various Internet Service Providers (ISPs). The results help you identify potential deliverability issues before you send to your entire contact list.
28 Apr 2025 - Mailjet.com
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How valuable are seed lists for email marketing and what are their limitations?
