What are the best pay-per-test tools for email deliverability and reputation validation?

Summary

A variety of resources and strategies exist for email deliverability and reputation validation, ranging from pay-per-test tools to free services and documentation. GlockApps offers pay-as-you-go testing. Free tools like SenderScore, Deliveryindex and Mail-Tester provide basic insights. Manual testing using seed lists is an option. Mailosaur can automate deliverability checks. MXToolbox offers diagnostic tools. Platforms like Sendgrid, Email on Acid, SparkPost, and Litmus provide features that aid deliverability. Authentication (SPF, DKIM, DMARC) is crucial. List management, content quality, sender reputation, and IP warmup are important factors. Google and Microsoft provide best practices for avoiding blocks.

Key findings

  • Pay-Per-Test Options: GlockApps provides pay-as-you-go deliverability testing.
  • Free Diagnostic Tools: SenderScore, Deliveryindex, and Mail-Tester offer free insights.
  • DIY Testing Strategies: Seed lists and manual analysis can be a cost-effective alternative.
  • Automation: Mailosaur provides automated testing via APIs.
  • Diagnostic Tools: MXToolbox offers blacklist and DNS checks for diagnostics.
  • Platform Features: Sendgrid, Email on Acid, SparkPost and Litmus provide deliverability features.
  • Authentication: SPF, DKIM, and DMARC are essential for email authentication.
  • Holistic Approach: Deliverability relies on managing list quality, content, and sender reputation.
  • IP Warmup: New IP addresses require careful warmup.
  • Provider Guidelines: Google and Microsoft provide best practices for deliverability.

Key considerations

  • Budget vs. Features: Balance the cost of paid tools with the insights gained.
  • Technical Expertise: Manual testing and diagnostic tools require technical expertise.
  • Ongoing Monitoring: Deliverability requires continuous monitoring and adjustment.
  • Long-Term Strategy: Build and maintain a positive sender reputation over time.
  • Holistic Approach: Take into account various factors, like IP warming, and authentication, for long-term delieverability

What email marketers say
13Marketer opinions

Various tools and strategies exist for assessing and improving email deliverability and reputation. GlockApps offers pay-as-you-go plans for deliverability testing. Free tools like SenderScore and Deliveryindex provide directional knowledge. Mail-Tester offers a free service with paid options. Building a custom seed list for manual analysis is another approach. Platforms like Email on Acid, SparkPost and Litmus offer features that help improve email delivery rates. Ensuring proper DKIM, SPF, and DMARC setup is critical, as is maintaining a clean email list and sender reputation.

Key opinions

  • GlockApps Pay-Per-Test: GlockApps offers pay-as-you-go deliverability tests, suitable for occasional testing needs.
  • Free Tools: SenderScore, Deliveryindex, and Mail-Tester provide free insights into deliverability.
  • DIY Testing: Creating a seed list and manually tracking inbox placement can be a cost-effective alternative.
  • Authentication is Crucial: Correct DKIM, SPF, and DMARC configuration is essential for email authentication and deliverability.
  • Platforms with deliverability features: Email on Acid, SparkPost and Litmus all offer features to improve deliverability.

Key considerations

  • Budget: Consider the budget when choosing between paid tools and free alternatives.
  • Testing Frequency: If testing is infrequent, pay-as-you-go options may be more economical.
  • Technical Expertise: Manual testing requires technical knowledge to set up and analyze seed lists.
  • Sender Reputation: Proactively manage sender reputation through authentication, list hygiene, and engagement monitoring.
  • Integration with existing platform: The deliverability tool should integrate seamlessly with the existing email marketing platform to provide a full testing cycle.
Marketer view

Email marketer from Email on Acid explains that pre-send testing tools like theirs are crucial for ensuring deliverability by checking rendering, accessibility, and deliverability factors. They offer various subscription plans that allow a certain number of tests per month, but does not directly do 'pay per test'.

January 2022 - Email On Acid
Marketer view

Marketer from Email Geeks provides a link to Senderscore.org as a free tool for gaining directional knowledge about deliverability.

January 2024 - Email Geeks
Marketer view

Marketer from Email Geeks mentions SendForensics, Unlock the Inbox, and MailMonitor (with a 2-month free trial). They also note that Mail-tester.com is useful for testing sender authentication and MXToolbox offers a quick SpamAssassin test.

November 2022 - Email Geeks
Marketer view

Email marketer from Mail-Tester.com explains that Mail-Tester provides a free service to analyze your email's content and headers for potential deliverability issues. While the core service is free, it provides valuable insights into factors affecting email placement, and it also offers paid plans with more features.

January 2024 - Mail-Tester.com
Marketer view

Email marketer from SparkPost answers that their platform helps to ensure deliverability. This includes implementing authentication protocols, monitoring reputation, and provides analytics on deliverability rates.

October 2021 - SparkPost
Marketer view

Marketer from Email Geeks shares that GlockApps offers a pay-per-test option, specifying that they are sold in blocks of tests (e.g., 50 tests in 90 days for a flat cost).

March 2025 - Email Geeks
Marketer view

Email marketer from Postmark provides a guide that details how to improve deliverability. The information includes, building an engaging list, using double opt-in, setting up SPF, DKIM and DMARC

September 2022 - Postmark
Marketer view

Marketer from Email Geeks shares Deliveryindex.org as another free deliverability tool.

February 2025 - Email Geeks
Marketer view

Email marketer from GlockApps.com explains that GlockApps offers pay-as-you-go plans that allow users to purchase email deliverability tests without a subscription, providing flexibility for occasional testing needs. These include options for single tests or small blocks of tests.

March 2025 - GlockApps.com
Marketer view

Email marketer from StackOverflow answers that ensuring DKIM, SPF, and DMARC setup is critical for email deliverability. Correctly configured DNS records authenticate emails, reducing the chances of being flagged as spam and improving inbox placement.

May 2022 - StackOverflow
Marketer view

Email marketer from Litmus shares that their platform offers email testing. This testing includes deliverability checks, spam filter testing, and inbox placement monitoring to ensure emails reach intended recipients.

January 2023 - Litmus
Marketer view

Email marketer from Reddit suggests building your own deliverability testing setup using a seed list and analyzing results manually across different providers to avoid recurring costs. This involves sending to various email providers and tracking inbox placement.

February 2024 - Reddit
Marketer view

Email marketer from Senderscore shares that the services provides a rating of your sending IP address and compares it to those of other email senders. This is a free and widely used method of measuring the reputation of email senders.

January 2025 - SenderScore

What the experts say
2Expert opinions

Email deliverability is significantly influenced by sender reputation, proper email authentication (SPF, DKIM, DMARC), and the quality of email content. Monitoring these factors and using feedback loops are crucial for improving sender reputation. For new IP addresses, a gradual IP warmup process involving increasing email volume and monitoring engagement is important to establish a positive reputation.

Key opinions

  • Key Deliverability Factors: Sender reputation, email authentication, and content quality are critical for deliverability.
  • IP Warmup: Gradual IP warmup is essential for new IP addresses to establish a positive sender reputation.
  • Monitoring and Feedback: Continuous monitoring of deliverability metrics and utilizing feedback loops are crucial for improvement.

Key considerations

  • Holistic Approach: Address all aspects of deliverability, including technical setup, content, and reputation management.
  • New IP Strategy: Implement a carefully planned IP warmup strategy for new sending IPs.
  • Ongoing Maintenance: Regularly monitor deliverability metrics and adapt strategies based on performance.
Expert view

Expert from Word to the Wise explains the importance of IP Warmup for improving your reputation with new IP addresses. She recommends the need to gradually increase email volume, while monitoring engagement to ensure that your IP is being delivered to the inbox.

May 2022 - Word to the Wise
Expert view

Expert from Spamresource.com explains that factors such as sender reputation, email authentication (SPF, DKIM, DMARC), and content quality significantly impact email deliverability. They recommend monitoring these elements and using feedback loops to improve sender reputation.

November 2021 - Spamresource.com

What the documentation says
5Technical articles

Email deliverability can be approached through several documented methods. Mailosaur offers automated testing using temporary email addresses and APIs. MXToolbox provides diagnostics including blacklist checks and DNS analysis, with more features in a subscription. Sendgrid highlights the importance of using dedicated IPs. Google emphasizes authentication, volume, and list management. Microsoft considers sender reputation, content, and authentication to determine email legitimacy, and notes that SPF, DKIM, and DMARC protocols are important.

Key findings

  • Mailosaur Automation: Mailosaur enables automated deliverability testing via temporary addresses and APIs.
  • MXToolbox Diagnostics: MXToolbox provides tools for diagnosing deliverability issues, including blacklist and DNS checks.
  • Sendgrid Dedicated IPs: Sendgrid offers dedicated IPs to help build sender reputation.
  • Google's Best Practices: Google recommends authentication, controlled sending volume, and list management to prevent blocking.
  • Microsoft's Multifactor Analysis: Microsoft assesses deliverability based on reputation, content, and authentication.

Key considerations

  • Testing Approach: Choose an automated testing tool like Mailosaur or manual diagnostics like MXToolbox.
  • Reputation Building: Consider dedicated IPs with Sendgrid and other methods to build a strong sender reputation.
  • Platform Requirements: Adhere to deliverability best practices recommended by major email providers like Google and Microsoft.
  • Cost of Advanced Features: Assess the need for paid services, such as dedicated IPs or advanced deliverability analytics.
Technical article

Documentation from MXToolbox.com explains that MXToolbox offers tools for diagnosing email deliverability issues, including blacklist checks, DNS record analysis, and SMTP diagnostics. While most basic tools are free, they provide comprehensive monitoring and alerting services on a subscription basis.

July 2021 - MXToolbox.com
Technical article

Documentation from Microsoft specifies that it uses multiple factors to determine whether incoming email is legitimate, including the sender's reputation, content of the message, and authentication. This also includes setting up SPF, DKIM and DMARC to improve email deliverability

December 2023 - Microsoft
Technical article

Documentation from Mailosaur.com explains Mailosaur can be used for automated email testing, including deliverability aspects, by providing temporary email addresses and APIs to analyze received emails. While not explicitly pay-per-test, it can be used in a controlled manner to monitor deliverability on a per-campaign basis.

April 2024 - Mailosaur.com
Technical article

Documentation from Google details the technical details on how to prevent mail to Gmail users from being blocked. This includes best practices for authentication, sending volume, and list management to maintain a positive sender reputation and ensure reliable delivery.

January 2024 - Google
Technical article

Documentation from Sendgrid details the features that ensure deliverability of emails sent from the platform. This also include the option to use a dedicated IP address which can help with building positive sender reputation.

January 2022 - Sendgrid