Mailspring vs Nullmailer
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?
| Feature | Mailspring | Nullmailer |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | GPL-3.0 | GPL-2.0 |
| Language | JavaScript | C++ |
| Setup difficulty | Easy | Easy |
| Min. RAM | 512 MB | 16 MB |
| Deployment | binary, source | bare-metal, source |
| GitHub stars | ★ 17,730 | ★ 199 |
| First released | 2017 | 2000 |
| Replaces | Outlook, Apple Mail | Sendmail |
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 Nullmailer better?
Neither is universally better. Mailspring has the larger community; both share a easy setup difficulty, so the decision comes down to features and licensing.
Are Mailspring and Nullmailer free and open-source?
Yes. Mailspring is licensed under GPL-3.0 and Nullmailer under GPL-2.0. Both can be self-hosted at no software cost.
Can I run Mailspring and Nullmailer with Docker?
Mailspring: check the project docs for container support. Nullmailer: check the project docs for container support.