Mail-in-a-Box vs msmtp
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?
Mail-in-a-Box
Turn a fresh server into a working mail server
VS
msmtp
Lightweight SMTP client for sending mail
| Feature | Mail-in-a-Box | msmtp |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | CC0-1.0 | GPL-3.0 |
| Language | Python | C |
| Setup difficulty | Easy | Easy |
| Min. RAM | 1,024 MB | 32 MB |
| Deployment | bare-metal, one-click | binary, source |
| GitHub stars | ★ 15,385 | ★ 290 |
| First released | 2014 | 2004 |
| Replaces | Google Workspace, Microsoft 365 | Sendmail |
Why pick each one
Choose msmtp if…
- Released under the GPL-3.0 license
- Easy to set up — beginner-friendly
- Written in C
- Tiny footprint — runs in 32 MB RAM
Frequently asked questions
Is Mail-in-a-Box or msmtp better?
Neither is universally better. Mail-in-a-Box has the larger community; both share a easy setup difficulty, so the decision comes down to features and licensing.
Are Mail-in-a-Box and msmtp free and open-source?
Yes. Mail-in-a-Box is licensed under CC0-1.0 and msmtp under GPL-3.0. Both can be self-hosted at no software cost.
Can I run Mail-in-a-Box and msmtp with Docker?
Mail-in-a-Box: check the project docs for container support. msmtp: check the project docs for container support.