Claws Mail vs Mail-in-a-Box
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?
Claws Mail
Lightweight and fast GTK email client
VS
Mail-in-a-Box
Turn a fresh server into a working mail server
| Feature | Claws Mail | Mail-in-a-Box |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | GPL-3.0 | CC0-1.0 |
| Language | C | Python |
| Setup difficulty | Easy | Easy |
| Min. RAM | 128 MB | 1,024 MB |
| Deployment | binary, source | bare-metal, one-click |
| GitHub stars | ★ 200 | ★ 15,385 |
| First released | 2001 | 2014 |
| Replaces | Microsoft Outlook | Google Workspace, Microsoft 365 |
Why pick each one
Choose Claws Mail if…
- Released under the GPL-3.0 license
- Easy to set up — beginner-friendly
- Written in C
- Tiny footprint — runs in 128 MB RAM
Frequently asked questions
Is Claws Mail or Mail-in-a-Box 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 Claws Mail and Mail-in-a-Box free and open-source?
Yes. Claws Mail is licensed under GPL-3.0 and Mail-in-a-Box under CC0-1.0. Both can be self-hosted at no software cost.
Can I run Claws Mail and Mail-in-a-Box with Docker?
Claws Mail: check the project docs for container support. Mail-in-a-Box: check the project docs for container support.