Mailu vs MailCatcher
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?
Mailu
Simple yet full-featured Docker mail server
VS
MailCatcher
Catch-all SMTP server for inspecting test email
| Feature | Mailu | MailCatcher |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | MIT | MIT |
| Language | Python | Ruby |
| Setup difficulty | Medium | Easy |
| Min. RAM | 2,048 MB | 128 MB |
| Deployment | docker, kubernetes | docker, binary, source |
| GitHub stars | ★ 7,443 | ★ 6,774 |
| First released | 2016 | 2010 |
| Replaces | Google Workspace, Microsoft 365 | Mailtrap |
Why pick each one
Choose MailCatcher if…
- Released under the MIT license
- Easy to set up — beginner-friendly
- First-class Docker support for quick deployment
- Mature project with 6.8k GitHub stars
Frequently asked questions
Is Mailu or MailCatcher better?
Neither is universally better. Mailu has the larger community, while MailCatcher is simpler to set up (easy difficulty). Choose based on the comparison table above and your own setup.
Are Mailu and MailCatcher free and open-source?
Yes. Mailu is licensed under MIT and MailCatcher under MIT. Both can be self-hosted at no software cost.
Can I run Mailu and MailCatcher with Docker?
Mailu: yes. MailCatcher: yes.