MailHog vs swaks
A side-by-side comparison of two self-hosted mail servers options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | MailHog | swaks |
|---|---|---|
| Deploy effort | Under-an-hour setup | Read-the-docs project |
| Health score | 26 · At risk | 15 · At risk |
| Category | Mail Servers | Mail Servers |
| License | MIT | GPL-2.0 |
| Language | Go | Perl |
| Setup difficulty | Easy | Easy |
| Min. RAM | 64 MB | 16 MB |
| Deployment | docker, binary, source | binary, source |
| GitHub stars | ★ 16,167 | ★ 1,344 |
| First released | 2014 | 2003 |
| Replaces | Mailtrap | Mailtrap |
What are MailHog and swaks?
MailHog
MailHog is an email testing tool that provides a fake SMTP server for developers, capturing messages and presenting them in a web UI. It includes an API and chaos-testing features.
- Fake SMTP for testing
- Web UI and JSON API
- Chaos monkey testing
- Single Go binary
swaks
swaks is a flexible command-line SMTP transaction tester used to diagnose and verify self-hosted mail servers. It can craft and send test messages with fine control over the SMTP conversation.
- Command-line SMTP tester
- Fine control over SMTP transactions
- Diagnoses mail server issues
MailHog vs swaks: key differences
MailHog is written in Go, while swaks is built with Perl. Licensing differs — MIT for MailHog versus GPL-2.0 for swaks. Swaks is the lighter option, starting around 16 MB of RAM against 64 MB for MailHog. Swaks is the more established project (first released 2003), while MailHog arrived in 2014. MailHog has the considerably larger community, at 16,167 GitHub stars versus 1,344. MailHog lists first-class Docker deployment; swaks does not.
Why pick each one
Choose MailHog if…
- Zero-config SMTP capture
- Handy web viewer
- Built-in chaos testing
Watch out for
- Development largely stalled
- Development use only
Choose swaks if…
- Released under the GPL-2.0 license
- Easy to set up — beginner-friendly
- Active community (1.3k GitHub stars)
- Written in Perl
Frequently asked questions
Is MailHog or swaks 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 swaks free and open-source?
Yes. MailHog is licensed under MIT and swaks under GPL-2.0. Both can be self-hosted at no software cost.
Can I run MailHog and swaks with Docker?
MailHog: yes. swaks: check the project docs for container support.
Which is lighter on resources, MailHog or swaks?
swaks has the smaller minimum footprint at 16 MB of RAM, compared to about 64 MB for MailHog. Real-world usage depends on library size, user count, and enabled features.