Mailspring vs OfflineIMAP

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?
FeatureMailspringOfflineIMAP
CategoryMail ServersMail Servers
LicenseGPL-3.0GPL-2.0
LanguageJavaScriptPython
Setup difficultyEasyMedium
Min. RAM512 MB64 MB
Deploymentbinary, sourcebinary, source
GitHub stars★ 17,730★ 631
First released20172002
ReplacesOutlook, Apple MailOutlook offline mode

Why pick each one

Choose Mailspring if…

  • Released under the GPL-3.0 license
  • Easy to set up — beginner-friendly
  • Mature project with 17.7k GitHub stars
  • Written in JavaScript
Mailspring details

Choose OfflineIMAP if…

  • Released under the GPL-2.0 license
  • Written in Python
  • Tiny footprint — runs in 64 MB RAM
OfflineIMAP details

Frequently asked questions

Is Mailspring or OfflineIMAP better?

Mailspring is the stronger all-round pick: it has both the larger community and the simpler easy setup. Consider OfflineIMAP if its specific feature set fits your needs better.

Are Mailspring and OfflineIMAP free and open-source?

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

Can I run Mailspring and OfflineIMAP with Docker?

Mailspring: check the project docs for container support. OfflineIMAP: check the project docs for container support.

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