# GreenMail vs MailSlurp

| Attribute | GreenMail | MailSlurp |
|---|---|---|
| **Vioscale score** | 58.2 (31% (low)) | 49.5 (54% (medium)) |
| activity.commits_last_30d | 28 | - |
| adoption.dependent_repos | 2,587 | - |
| adoption.github_stars | 740 | - |
| deployment.options | `{"self_hosted":true}` | `{"cloud":true}` |
| description.long | 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. | A testing and automation platform providing real email inboxes and phone numbers via APIs and SDKs, enabling developers to verify email flows, OTP delivery, and message behavior in automated tests and CI/CD pipelines. |
| features.capabilities | `{"open_source":true,"sms_testing":false,"api_assertions":true,"spam_score_check":false,"ci_cd_integration":true,"rendering_preview":false,"multi_user_inboxes":true,"production_sending_addon":false,"blocklist_deliverability_check":false}` | `{"open_source":false,"sms_testing":true,"api_assertions":true,"spam_score_check":true,"ci_cd_integration":true,"rendering_preview":true,"multi_user_inboxes":true,"production_sending_addon":true,"blocklist_deliverability_check":true}` |
| integrations.count | - | 8 |
| integrations.list | - | `[{"name":"Zapier"},{"name":"Gmail"},{"name":"Outlook"},{"name":"Dropbox"},{"name":"Google Drive"},{"name":"Playwright"},{"name":"CypressJS"},{"name":"ACCELQ"}]` |
| language.primary | Java | - |
| license.spdx | Apache-2.0 | - |
| platform.support | - | `{"web":true}` |
| pricing | `{"type":"open_source","freeTier":true,"sourceUrl":"https://greenmail-mail-test.github.io/greenmail/","retrievedAt":"2026-08-21T12:46:10.376Z"}` | `{"freeTier":true,"sourceUrl":"https://www.mailslurp.com/compare/sendgrid-pricing/","retrievedAt":"2026-08-25T12:11:49.908Z"}` |
| pricing.free_tier | yes | yes |
| pricing.model | commercial | freemium |
| pricing.price_level | free | low |
| pricing.transparent | - | no |
| release.cadence_days | 43 | - |
| release.history | `[{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.13","date":"2026-08-23T10:02:24Z","type":"stable","version":"release-2.1.13"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.12","date":"2026-08-05T18:50:04Z","type":"stable","version":"release-2.1.12"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.11","date":"2026-07-15T19:46:18Z","type":"stable","version":"release-2.1.11"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.10","date":"2026-07-14T09:57:41Z","type":"stable","version":"release-2.1.10"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.9","date":"2026-06-14T17:01:37Z","type":"stable","version":"release-2.1.9"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.8","date":"2025-12-14T17:26:41Z","type":"stable","version":"release-2.1.8"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.7","date":"2025-10-07T21:21:09Z","type":"stable","version":"release-2.1.7"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.6","date":"2025-09-28T18:47:25Z","type":"stable","version":"release-2.1.6"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.5","date":"2025-08-10T18:41:13Z","type":"stable","version":"release-2.1.5"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.4","date":"2025-07-13T16:54:29Z","type":"stable","version":"release-2.1.4"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.3","date":"2025-02-04T20:59:33Z","type":"stable","version":"release-2.1.3"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.2","date":"2024-11-30T11:21:39Z","type":"stable","version":"release-2.1.2"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.1","date":"2024-11-17T21:12:57Z","type":"stable","version":"release-2.1.1"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.0","date":"2024-10-05T16:20:21Z","type":"stable","version":"release-2.1.0"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.0-rc-1","date":"2024-05-31T20:05:52Z","type":"stable","version":"release-2.1.0-rc-1"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.0-alpha-4","date":"2024-01-28T18:47:27Z","type":"stable","version":"release-2.1.0-alpha-4"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-1.6.15","date":"2023-12-03T15:51:55Z","type":"stable","version":"release-1.6.15"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.0.1","date":"2023-11-17T21:42:15Z","type":"stable","version":"release-2.0.1"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.0-alpha-3","date":"2023-11-04T13:17:06Z","type":"stable","version":"release-2.1.0-alpha-3"},{"url":"https://github.com/greenmail-mail-test/greenmail/releases/tag/release-2.1.0-alpha-2","date":"2023-08-20T20:17:02Z","type":"stable","version":"release-2.1.0-alpha-2"}]` | - |
| security.scorecard | 6.4 | - |
| security.soc2 | - | yes |
| security.vulnerabilities | `{"count":0,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=maven&package_name=com.icegreen%3Agreenmail&per_page=100","last_12m":0,"max_severity":null}` | - |

## Capabilities (Email Testing Dev)

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

*Source: Vioscale. Generated 2026-09-01T16:39:32.063Z. "-" = undocumented, not absent.*