# Maildev vs MailSlurp

| Attribute | Maildev | MailSlurp |
|---|---|---|
| **Vioscale score** | 63.8 (24% (low)) | 49.5 (54% (medium)) |
| activity.commits_last_30d | 24 | - |
| adoption.dependent_repos | 313 | - |
| adoption.github_stars | 6,032 | - |
| deployment.options | `{"self_hosted":true}` | `{"cloud":true}` |
| description.long | Runs as a local SMTP server with a web inbox interface to capture and review emails generated by your application during development. Supports AI agent integration through the Model Context Protocol for automated email inspection. | 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":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 | TypeScript | - |
| license.spdx | MIT | - |
| platform.support | `{"cli":true,"web":true}` | `{"web":true}` |
| pricing | `{"type":"free","summary":"Free & open source (MIT)","freeTier":true,"sourceUrl":"https://maildev.github.io/maildev/","retrievedAt":"2026-08-20T16:30:07.523Z"}` | `{"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 | yes | no |
| release.cadence_days | 46 | - |
| release.history | `[{"url":"https://github.com/maildev/maildev/releases/tag/maildev%403.0.0-rc.1","date":"2026-07-06T19:40:50Z","type":"stable","version":"maildev@3.0.0-rc.1"},{"url":"https://github.com/maildev/maildev/releases/tag/v2.2.1","date":"2024-12-12T02:09:20Z","type":"stable","version":"v2.2.1"},{"url":"https://github.com/maildev/maildev/releases/tag/v2.1.0","date":"2023-07-20T01:57:33Z","type":"stable","version":"v2.1.0"},{"url":"https://github.com/maildev/maildev/releases/tag/v2.0.5","date":"2022-05-18T16:10:38Z","type":"stable","version":"v2.0.5"},{"url":"https://github.com/maildev/maildev/releases/tag/v2.0.4","date":"2022-05-17T21:24:00Z","type":"stable","version":"v2.0.4"},{"url":"https://github.com/maildev/maildev/releases/tag/v2.0.2","date":"2022-03-23T07:56:47Z","type":"stable","version":"v2.0.2"},{"url":"https://github.com/maildev/maildev/releases/tag/v2.0.1","date":"2022-03-23T03:43:18Z","type":"stable","version":"v2.0.1"},{"url":"https://github.com/maildev/maildev/releases/tag/v2.0.0","date":"2022-03-22T16:22:09Z","type":"stable","version":"v2.0.0"},{"url":"https://github.com/maildev/maildev/releases/tag/v1.1.1","date":"2022-03-22T16:08:54Z","type":"stable","version":"v1.1.1"},{"url":"https://github.com/maildev/maildev/releases/tag/v1.1.0","date":"2019-07-27T21:57:24Z","type":"stable","version":"v1.1.0"},{"url":"https://github.com/maildev/maildev/releases/tag/1.0.0","date":"2019-03-19T02:36:24Z","type":"stable","version":"1.0.0"},{"url":"https://github.com/maildev/maildev/releases/tag/0.14.0","date":"2016-08-13T16:24:32Z","type":"stable","version":"0.14.0"},{"url":"https://github.com/maildev/maildev/releases/tag/0.13.4","date":"2016-07-01T22:58:28Z","type":"stable","version":"0.13.4"},{"url":"https://github.com/maildev/maildev/releases/tag/0.13.3","date":"2016-05-16T04:11:12Z","type":"stable","version":"0.13.3"},{"url":"https://github.com/maildev/maildev/releases/tag/0.13.2","date":"2016-05-14T18:25:02Z","type":"stable","version":"0.13.2"},{"url":"https://github.com/maildev/maildev/releases/tag/0.13.1","date":"2016-04-22T03:17:26Z","type":"stable","version":"0.13.1"},{"url":"https://github.com/maildev/maildev/releases/tag/0.13.0","date":"2016-03-20T20:45:31Z","type":"stable","version":"0.13.0"},{"url":"https://github.com/maildev/maildev/releases/tag/0.12.2","date":"2016-03-08T03:05:13Z","type":"stable","version":"0.12.2"},{"url":"https://github.com/maildev/maildev/releases/tag/0.12.1","date":"2015-11-07T23:18:35Z","type":"stable","version":"0.12.1"},{"url":"https://github.com/maildev/maildev/releases/tag/0.12.0","date":"2015-08-26T04:51:51Z","type":"stable","version":"0.12.0"}]` | - |
| security.scorecard | 4.6 | - |
| security.soc2 | - | yes |
| security.vulnerabilities | `{"count":1,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=npm&package_name=maildev&per_page=100","last_12m":0,"max_severity":"CRITICAL"}` | - |

## Capabilities (Email Testing Dev)

| Capability | Maildev | 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 2026-09-01T16:50:52.781Z. "-" = undocumented, not absent.*