Mailspring vs OpenSMTPD
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?
Mailspring
Cross-platform desktop email client
VS
OpenSMTPD
Secure and simple SMTP server from OpenBSD
| Feature | Mailspring | OpenSMTPD |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | GPL-3.0 | ISC |
| Language | JavaScript | C |
| Setup difficulty | Easy | Medium |
| Min. RAM | 512 MB | 32 MB |
| Deployment | binary, source | bare-metal, source |
| GitHub stars | ★ 17,730 | ★ 579 |
| First released | 2017 | 2013 |
| Replaces | Outlook, Apple Mail | Sendmail, Postfix |
Why pick each one
Choose Mailspring if…
- Released under the GPL-3.0 license
- Easy to set up — beginner-friendly
- Mature project with 17.7k GitHub stars
- Written in JavaScript
Frequently asked questions
Is Mailspring or OpenSMTPD better?
Mailspring is the stronger all-round pick: it has both the larger community and the simpler easy setup. Consider OpenSMTPD if its specific feature set fits your needs better.
Are Mailspring and OpenSMTPD free and open-source?
Yes. Mailspring is licensed under GPL-3.0 and OpenSMTPD under ISC. Both can be self-hosted at no software cost.
Can I run Mailspring and OpenSMTPD with Docker?
Mailspring: check the project docs for container support. OpenSMTPD: check the project docs for container support.