msmtp 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?
FeaturemsmtpNullmailer
CategoryMail ServersMail Servers
LicenseGPL-3.0GPL-2.0
LanguageCC++
Setup difficultyEasyEasy
Min. RAM32 MB16 MB
Deploymentbinary, sourcebare-metal, source
GitHub stars★ 290★ 199
First released20042000
ReplacesSendmailSendmail

Why pick each one

Choose msmtp if…

  • Released under the GPL-3.0 license
  • Easy to set up — beginner-friendly
  • Written in C
  • Tiny footprint — runs in 32 MB RAM
msmtp details

Choose Nullmailer if…

  • Extremely lightweight
  • Simple configuration
Nullmailer details

Frequently asked questions

Is msmtp or Nullmailer better?

Neither is universally better. msmtp has the larger community; both share a easy setup difficulty, so the decision comes down to features and licensing.

Are msmtp and Nullmailer free and open-source?

Yes. msmtp is licensed under GPL-3.0 and Nullmailer under GPL-2.0. Both can be self-hosted at no software cost.

Can I run msmtp and Nullmailer with Docker?

msmtp: check the project docs for container support. Nullmailer: check the project docs for container support.

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