Alf.io vs Horde Kronolith
A side-by-side comparison of two self-hosted calendar & contacts options — licensing, setup difficulty, resource needs, and what each one replaces.
Not the right match-up?
Alf.io
Ticket reservation system
VS
Horde Kronolith
Calendar application from the Horde groupware suite
| Feature | Alf.io | Horde Kronolith |
|---|---|---|
| Category | Calendar & Contacts | Calendar & Contacts |
| License | GPL-3.0 | GPL-2.0 |
| Language | Java | PHP |
| Setup difficulty | Medium | Hard |
| Min. RAM | 512 MB | 256 MB |
| Deployment | bare-metal | bare-metal |
| GitHub stars | ★ 1,601 | ★ 10 |
| First released | 2025 | 2003 |
| Replaces | — | Google Calendar, Exchange |
Why pick each one
Choose Alf.io if…
- Released under the GPL-3.0 license
- Active community (1.6k GitHub stars)
- Written in Java
- Lightweight — runs in 512 MB RAM
Choose Horde Kronolith if…
- Released under the GPL-2.0 license
- Written in PHP
- Tiny footprint — runs in 256 MB RAM
Frequently asked questions
Is Alf.io or Horde Kronolith better?
Alf.io is the stronger all-round pick: it has both the larger community and the simpler medium setup. Consider Horde Kronolith if its specific feature set fits your needs better.
Are Alf.io and Horde Kronolith free and open-source?
Yes. Alf.io is licensed under GPL-3.0 and Horde Kronolith under GPL-2.0. Both can be self-hosted at no software cost.
Can I run Alf.io and Horde Kronolith with Docker?
Alf.io: check the project docs for container support. Horde Kronolith: check the project docs for container support.