MailHog 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?
MailHog
Email testing tool with a fake SMTP server
VS
Nullmailer
Simple relay-only mail transfer agent
| Feature | MailHog | Nullmailer |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | MIT | GPL-2.0 |
| Language | Go | C++ |
| Setup difficulty | Easy | Easy |
| Min. RAM | 64 MB | 16 MB |
| Deployment | docker, binary, source | bare-metal, source |
| GitHub stars | ★ 16,107 | ★ 199 |
| First released | 2014 | 2000 |
| Replaces | Mailtrap | Sendmail |
Why pick each one
Choose MailHog if…
- Released under the MIT license
- Easy to set up — beginner-friendly
- First-class Docker support for quick deployment
- Mature project with 16.1k GitHub stars
Frequently asked questions
Is MailHog or Nullmailer better?
Neither is universally better. MailHog has the larger community; both share a easy setup difficulty, so the decision comes down to features and licensing.
Are MailHog and Nullmailer free and open-source?
Yes. MailHog is licensed under MIT and Nullmailer under GPL-2.0. Both can be self-hosted at no software cost.
Can I run MailHog and Nullmailer with Docker?
MailHog: yes. Nullmailer: check the project docs for container support.