vioscale
Comparison

GreenMail vs Mailosaur

No clear leader: Mailosaur (60.5) and GreenMail (58.2) 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.

GreenMail full profile →Mailosaur full profile →
Machine formatsJSONMarkdownGraphQLor send Accept: application/json
GreenMail58
Mailosaur61
Score
Vioscale score
GreenMail58 / 100low · 31%
Mailosaur61 / 100medium · 55%
Pricing
Free tier
GreenMail✓
Mailosaur✗
Model
GreenMailcommercial
Mailosaurcommercial
Price level
GreenMailfree
Mailosaurmid
Starting price
GreenMail–
Mailosaur$20
Transparent
GreenMail–
Mailosaur✓
Integrations
Count
GreenMail–
Mailosaur20
Security
Disclosure policy
GreenMail–
Mailosaur✓
Gdpr
GreenMail–
Mailosaur✓
Iso27001
GreenMail–
Mailosaur✓
Pci
GreenMail–
Mailosaur✓
Scorecard
GreenMail6.4
Mailosaur–
Vulnerabilities
Adoption
Dependent repos
GreenMail2,587
Mailosaur–
Github stars
GreenMail740
Mailosaur–
Activity
Commits last 30d
GreenMail28
Mailosaur–
Release
Cadence days
GreenMail43
Mailosaur–
History
GreenMail20 items
Mailosaur–
License
Spdx
GreenMailApache-2.0
Mailosaur–
Language
Primary
GreenMailJava
Mailosaur–
Market
Availability

Capabilities

Feature-by-feature on the axes that matter for email testing dev. “-” means undocumented, not absent.

Capabilities
API assertions
GreenMail✓
Mailosaur✓
Rendering preview
GreenMail✗
Mailosaur✓
Spam score check
GreenMail✗
Mailosaur✓
Blocklist deliverability check
GreenMail✗
Mailosaur-
SMS testing
GreenMail✗
Mailosaur✓
Production sending addon
GreenMail✗
Mailosaur-
Ci cd integration
GreenMail✓
Mailosaur✓
Multi user inboxes
GreenMail✓
Mailosaur✓
Open source
GreenMail✓
Mailosaur-

What each one is

The product in its own terms, so the numbers below have context.

GreenMail

A testing framework that emulates email server behavior (SMTP, POP3, IMAP) to help developers verify email functionality in their applications during testing, without requiring actual email infrastructure or sending real messages.

Independently observed

Mailosaur

Provides tools for validating emails and SMS messages through dedicated inboxes and phone numbers, with rendering previews across devices and email clients, integration into CI/CD pipelines, and automation via APIs and testing framework support.

Independently observed

Pricing

List pricing as published by each vendor, with the date we read it. Always verify at the source before you buy.

GreenMail

Open sourceFree tier
as of verify ↗

Mailosaur

from $20/moSubscription14-day trial

From $20/month (billed annually). Free 14-day trial.

  • Personal$20/month (billed annually)
    • Email compatibility testing
    • API for test automation
    • Forward emails to external addresses
  • Core$50/month (popular)
    • Team access
    • Multiple inboxes
    • Email accessibility testing
    • Mail rules
    • POP3/IMAP connectivity
    • +1 more
  • EnterpriseContact sales
    • Custom users and inboxes
    • SSO (SAML2/OIDC)
    • Separate permissions
    • Enterprise security
    • Account manager
    • +1 more
as of verify ↗

Platform & deployment

Where each product runs and how it can be hosted. A dash means undocumented, not unsupported.

Platforms
Web
GreenMail–
Mailosaur✓
CLI
GreenMail–
Mailosaur✓
Deployment
Cloud / SaaS
GreenMail✗
Mailosaur✓
Self-hosted
GreenMail✓
Mailosaur✗

Integrations

What each product connects to. Counts come from the vendor's own integration directory where one exists.

GreenMail

Not documented yet.

Mailosaur

21 total
  • 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
Independently observed

Comparison generated from independently-sourced facts. Every value links to its source and retrieval date. See the method.