Compare software

Cyrus IMAPWildDuck
Free

Free and open source.

 Free

Free open-source software that you host yourself.

Linux, Self-hosted Linux, Self-hosted
  • Mail, calendars and contacts in one server
  • JMAP support alongside IMAP
  • Horizontal scaling with no single point of failure
  • Full IMAP4rev1 support with many extensions
  • Complex to configure compared with all-in-one servers
  • No bundled webmail
  • Needs MongoDB, Redis and separate SMTP components
  • Aimed at large deployments rather than small personal servers
Self-hosted Self-hosted
Open source Open source
License not stated License not stated
No account needed Not stated if an account is needed
Not stated if it works offline Not stated if it works offline

Checked September 24, 2026

Checked October 1, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.