GreenMail vs Mailosaur
No clear leader: Mailosaur (60.5) and GreenMail (55.9) are within the 5-point margin; treat as a tie. The attribute-by-attribute breakdown below, with a source and date on every value, is the honest way to compare them.
Capabilities
Feature-by-feature on the axes that matter for email testing dev. “-” means undocumented, not absent.
What each one is
The product in its own terms, so the numbers below have context.
GreenMail
GreenMail is a lightweight testing tool that simulates SMTP, POP3, and IMAP email servers for application testing. It allows developers to extract, verify, and modify test messages within a contained environment while supporting SSL encryption.
Mailosaur
Mailosaur enables development and QA teams to test emails and SMS messages end-to-end with real-device message previews across email clients and devices. The platform supports test automation through APIs and integrations with popular testing frameworks, eliminating the need for dummy accounts or manual testing.
Pricing
List pricing as published by each vendor, with the date we read it. Always verify at the source before you buy.
Mailosaur
From $20/month billed annually. 14-day free trial available.
- Personal$20/month billed annually
- Unlimited email addresses per inbox
- Email compatibility testing
- API for test automation
- Email forwarding to external addresses
- Core$50/month
- Multiple inboxes with unlimited email addresses
- Team access and collaboration
- Email accessibility testing
- Email forwarding and reply functionality
- POP3 and IMAP connectivity
- +1 more
- EnterpriseContact sales
- Custom user and inbox configuration
- Team and project-level permission separation
- Single Sign-On (SAML2 and OIDC)
- Enterprise security features (SCIM, custom session timeouts)
- Dedicated account manager
- +3 more
Platform & deployment
Where each product runs and how it can be hosted. A dash means undocumented, not unsupported.
Integrations
What each product connects to. Counts come from the vendor's own integration directory where one exists.
GreenMail
Not documented yet.
Mailosaur
- Selenium
- Playwright
- Cypress
- TestCafe
- WebdriverIO
- Cucumber
- Robot Framework
- Ghost Inspector
- Postman
- Insomnia
- PowerShell
- Node.js
- Java
- Python
- Ruby
- .NET
- PHP
- Go
- JavaScript
- Okta
- Microsoft Entra
GreenMail or Mailosaur: which one depends on you
A composite score cannot know your constraints. Describe them and both get re-weighted against what you actually need, with the evidence behind every position.
Free to run, no account needed to start. How the evaluation works
Comparison generated from independently-sourced facts. Every value links to its source and retrieval date. See the method.