Docker Mailserver vs Sendmail
A side-by-side comparison of two self-hosted mail servers options — licensing, setup difficulty, resource needs, and what each one replaces.
Not the right match-up?
Docker Mailserver
Production-ready, config-driven mail server in a container
VS
Sendmail
Message transfer agent (MTA)
| Feature | Docker Mailserver | Sendmail |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | MIT | Sendmail |
| Language | Shell | C |
| Setup difficulty | Medium | Medium |
| Min. RAM | 2,048 MB | 512 MB |
| Deployment | docker | bare-metal |
| GitHub stars | ★ 18,682 | — |
| First released | 2015 | 2020 |
| Replaces | Google Workspace, Microsoft 365 | — |
Why pick each one
Choose Docker Mailserver if…
- Reproducible, version-controllable config
- Lightweight
Choose Sendmail if…
- Released under the Sendmail license
- Written in C
- Lightweight — runs in 512 MB RAM
Frequently asked questions
Is Docker Mailserver or Sendmail better?
Neither is universally better. Docker Mailserver has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.
Are Docker Mailserver and Sendmail free and open-source?
Yes. Docker Mailserver is licensed under MIT and Sendmail under Sendmail. Both can be self-hosted at no software cost.
Can I run Docker Mailserver and Sendmail with Docker?
Docker Mailserver: yes. Sendmail: check the project docs for container support.