Cal.diy vs KOrganizer
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?
Cal.diy
Online appointment scheduling system
VS
KOrganizer
Calendar and scheduling component of KDE Kontact
| Feature | Cal.diy | KOrganizer |
|---|---|---|
| Category | Calendar & Contacts | Calendar & Contacts |
| License | MIT | GPL-2.0 |
| Language | TypeScript | C++ |
| Setup difficulty | Medium | Medium |
| Min. RAM | 512 MB | 512 MB |
| Deployment | bare-metal | binary, source |
| GitHub stars | ★ 47,334 | ★ 100 |
| First released | 2026 | 2000 |
| Replaces | — | Outlook Calendar |
Why pick each one
Choose Cal.diy if…
- Released under the MIT license
- Mature project with 47.3k GitHub stars
- Written in TypeScript
- Lightweight — runs in 512 MB RAM
Choose KOrganizer if…
- Released under the GPL-2.0 license
- Written in C++
- Lightweight — runs in 512 MB RAM
Frequently asked questions
Is Cal.diy or KOrganizer better?
Neither is universally better. Cal.diy has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.
Are Cal.diy and KOrganizer free and open-source?
Yes. Cal.diy is licensed under MIT and KOrganizer under GPL-2.0. Both can be self-hosted at no software cost.
Can I run Cal.diy and KOrganizer with Docker?
Cal.diy: check the project docs for container support. KOrganizer: check the project docs for container support.