# Maildev vs Mailosaur

| Attribute | Maildev | Mailosaur |
|---|---|---|
| **Vioscale score** | 63.8 (24% (low)) | 60.5 (55% (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. | 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. |
| features.capabilities | - | `{"sms_testing":true,"api_assertions":true,"spam_score_check":true,"ci_cd_integration":true,"rendering_preview":true,"multi_user_inboxes":true}` |
| integrations.count | - | 20 |
| integrations.list | - | `[{"name":"Selenium"},{"name":"Playwright"},{"name":"Cypress"},{"name":"TestCafe"},{"name":"WebdriverIO"},{"name":"Cucumber"},{"name":"Robot Framework"},{"name":"Ghost Inspector"},{"name":"Postman"},{"name":"Insomnia"},{"name":"PowerShell"},{"name":"Node.js"},{"name":"Java"},{"name":"Python"},{"name":"Ruby"},{"name":".NET"},{"name":"PHP"},{"name":"Go"},{"name":"JavaScript"},{"name":"Okta"},{"name":"Microsoft Entra"}]` |
| language.primary | TypeScript | - |
| license.spdx | MIT | - |
| market.availability | - | `{"hqCountry":"GB","primaryMarkets":["GB","US"],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` |
| platform.support | `{"cli":true,"web":true}` | `{"cli":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"}` | `{"type":"subscription","plans":[{"free":false,"name":"Personal","summary":"$20/month (billed annually)","features":["Email compatibility testing","API for test automation","Forward emails to external addresses"],"minSeats":1,"components":[{"kind":"fixed","amount":20,"period":"month","currency":"USD"}],"description":"For individuals requiring email testing essentials","contactSales":false,"includedLimits":{"users":"1 (support for up to 3)","inboxes":"1","emails_per_month":"15,000"}},{"free":false,"name":"Core","summary":"$50/month (popular)","features":["Team access","Multiple inboxes","Email accessibility testing","Mail rules","POP3/IMAP connectivity","SMS support"],"minSeats":5,"components":[{"kind":"fixed","amount":50,"period":"month","currency":"USD"}],"description":"Collaborative testing scaled for teams","contactSales":false,"includedLimits":{"users":"5 seats","emails_per_month":"75,000"}},{"free":false,"name":"Enterprise","features":["Custom users and inboxes","SSO (SAML2/OIDC)","Separate permissions","Enterprise security","Account manager","Advanced support with SLAs"],"contactSales":true}],"addOns":[{"name":"SMS and authentication","components":[{"kind":"fixed","amount":37.5,"period":"month","currency":"USD"}]},{"name":"Email previews","components":[{"kind":"fixed","amount":25,"period":"month","currency":"USD"}]}],"summary":"From $20/month (billed annually). Free 14-day trial.","currency":"USD","freeTier":false,"sourceUrl":"https://mailosaur.com/pricing","retrievedAt":"2026-08-25T12:08:17.001Z","freeTrialDays":14,"startingPrice":{"amount":20,"period":"month","currency":"USD"},"billingPeriods":["month","year"]}` |
| pricing.free_tier | yes | no |
| pricing.model | commercial | commercial |
| pricing.price_level | free | mid |
| pricing.starting_price | - | `{"amount":20,"currency":"USD"}` |
| pricing.transparent | yes | yes |
| 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.disclosure_policy | - | yes |
| security.gdpr | - | yes |
| security.iso27001 | - | yes |
| security.pci | - | yes |
| security.scorecard | 4.6 | - |
| 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 | Mailosaur |
|---|:--:|:--:|
| **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 2026-09-01T16:51:05.265Z. "-" = undocumented, not absent.*