MailDev

6.6easy start · #15 of 28
in Email Testing Software

Free to practise onyes
Free trialnot on record
Well documentedyes
Runs where you worknot on record

Runs on api, self-hosted, Web.

MailDev is ranked #15 of 28 in email testing software on The Geeks Club. It runs on API, Self-hosted, Web. There is a free plan.

MailDev plans and pricing

All plans

MailDev Free Free and open source · MIT licensed · Runs locally maildev.github.io · 5 Oct 2026

Compared on email testing software

Free plan: Yes
API access: Yes

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The record

Purpose: MailDev is a local SMTP server and web inbox for developers to catch and inspect email sent by an app during development.
Email formats: The inbox displays rendered HTML, plain text, headers, and raw email source.
Preview: The web interface offers a responsive preview for checking how email renders at different viewport widths.
SMTP and API: MailDev listens for SMTP on port 1025 and provides a REST API under `/api` for listing, reading, searching, downloading, and deleting mail.
Live updates: New messages appear in the inbox over WebSockets without a refresh or polling.
Framework integrations: The docs provide setup examples for Nodemailer, Django, Ruby on Rails, Laravel, and Spring Boot, and say any language that speaks SMTP can connect.
AI integration: MailDev includes an optional MCP server that lets compatible AI clients search and read the development inbox and check email delivery.
Install options: The maker documents running MailDev with npx, a global npm install, or Docker.
Relay: MailDev can selectively relay messages through a configured outgoing SMTP server, with optional auto-relay rules.
Security: MailDev accepts mail from anyone, stores it unencrypted, and has no authentication by default, so the docs warn against exposing it to the public internet or using it for production traffic.
Email retention: MailDev keeps emails without a configured limit by default; its `--max-emails` option can cap the inbox and discard older messages.
Audience: The maker describes MailDev as a development tool for developers testing email generated by their projects.
Price from: Free

Where it ranks on The Geeks Club

Best Email Testing Software in 2026#15 of 28

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Sources

maildev.github.io/maildev/docs/· checked 5 Oct 2026
maildev.github.io/maildev/· checked 5 Oct 2026
maildev.github.io/maildev/docs/quickstart/· checked 5 Oct 2026
maildev.github.io/maildev/docs/ai/mcp/· checked 5 Oct 2026
github.com/maildev/maildev· checked 5 Oct 2026