Mailu vs mailcow
A side-by-side comparison of two self-hosted mail servers options — licensing, setup difficulty, resource needs, and what each one replaces.
mailcow
Dockerized full-stack mail server suite
| Feature | Mailu | mailcow |
|---|---|---|
| Deploy effort | Under-an-hour setup | Under-an-hour setup |
| Health score | 91 · Excellent | 94 · Excellent |
| Category | Mail Servers | Mail Servers |
| License | MIT | GPL-3.0 |
| Language | Python | JavaScript |
| Setup difficulty | Medium | Medium |
| Min. RAM | 2,048 MB | 6,144 MB |
| Deployment | docker, kubernetes | docker |
| GitHub stars | ★ 7,524 | ★ 13,498 |
| First released | 2016 | 2016 |
| Replaces | Google Workspace, Microsoft 365 | Microsoft Exchange, Google Workspace |
What are Mailu and mailcow?
Mailu
Mailu is a free mail server distributed as a set of Docker images, providing a complete stack with antispam, webmail, and admin interface. It aims to be simpler and lighter than other mail suites.
- Composable Docker images
- Built-in antispam and antivirus
- Roundcube and SnappyMail webmail
- Admin UI and REST API
mailcow
mailcow is a complete, Docker-based mail server solution that bundles Postfix, Dovecot, Rspamd, SOGo, and a modern web UI. It makes running a full-featured mail server with antispam and webmail straightforward.
- Complete Docker mail stack
- Rspamd antispam built in
- SOGo webmail and ActiveSync
- Modern management UI with API
Mailu vs mailcow: key differences
Mailu is written in Python, while mailcow is built with JavaScript. Licensing differs — MIT for Mailu versus GPL-3.0 for mailcow. Mailu is the lighter option, starting around 2,048 MB of RAM against 6,144 MB for mailcow.
Why pick each one
Choose Mailu if…
- Lighter than mailcow
- Kubernetes support
Watch out for
- Fewer features than larger suites
- Manual DNS configuration
Choose mailcow if…
- All components preconfigured
- Active community
Watch out for
- Substantial RAM requirements
- Many containers to manage
Frequently asked questions
Is Mailu or mailcow better?
Neither is universally better. mailcow has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.
Are Mailu and mailcow free and open-source?
Yes. Mailu is licensed under MIT and mailcow under GPL-3.0. Both can be self-hosted at no software cost.
Can I run Mailu and mailcow with Docker?
Mailu: yes. mailcow: yes.
Which is lighter on resources, Mailu or mailcow?
Mailu has the smaller minimum footprint at 2,048 MB of RAM, compared to about 6,144 MB for mailcow. Real-world usage depends on library size, user count, and enabled features.