Mailpit 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 | Mailpit | swaks |
|---|---|---|
| Deploy effort | Under-an-hour setup | Read-the-docs project |
| Health score | 93 · Excellent | 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 | binary, source |
| GitHub stars | ★ 10,426 | ★ 1,344 |
| First released | 2022 | 2003 |
| Replaces | Mailtrap, MailHog | Mailtrap |
What are Mailpit and swaks?
Mailpit
Mailpit is a self-hosted email testing tool that acts as an SMTP server and captures all messages for inspection in a clean web interface. Developers use it to preview and debug application email locally.
- SMTP capture server
- Web message viewer
- REST API
- HTML and link checks
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
Mailpit vs swaks: key differences
Mailpit is written in Go, while swaks is built with Perl. Licensing differs — MIT for Mailpit versus GPL-2.0 for swaks. Swaks is the lighter option, starting around 16 MB of RAM against 64 MB for Mailpit. Swaks is the more established project (first released 2003), while Mailpit arrived in 2022. Mailpit has the considerably larger community, at 10,426 GitHub stars versus 1,344. Mailpit lists first-class Docker deployment; swaks does not.
Why pick each one
Choose Mailpit if…
- Very fast and small
- Great developer UX
Watch out for
- For testing not production
- Not a real mail server
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 Mailpit or swaks better?
Neither is universally better. Mailpit has the larger community; both share a easy setup difficulty, so the decision comes down to features and licensing.
Are Mailpit and swaks free and open-source?
Yes. Mailpit is licensed under MIT and swaks under GPL-2.0. Both can be self-hosted at no software cost.
Can I run Mailpit and swaks with Docker?
Mailpit: yes. swaks: check the project docs for container support.
Which is lighter on resources, Mailpit or swaks?
swaks has the smaller minimum footprint at 16 MB of RAM, compared to about 64 MB for Mailpit. Real-world usage depends on library size, user count, and enabled features.