Claws Mail vs hash-calendar
A side-by-side comparison of two self-hosted apps from related categories — licensing, setup difficulty, resource needs, and what each one replaces.
Not the right match-up?
Claws Mail
Lightweight and fast GTK email client
VS
hash-calendar
Lightweight calendar app where the data lives in the URL hash
| Feature | Claws Mail | hash-calendar |
|---|---|---|
| Category | Mail Servers | File Sync & Storage |
| License | GPL-3.0 | MIT |
| Language | C | JavaScript |
| Setup difficulty | Easy | Medium |
| Min. RAM | 128 MB | 512 MB |
| Deployment | binary, source | bare-metal |
| GitHub stars | ★ 200 | ★ 69 |
| First released | 2001 | 2026 |
| Replaces | Microsoft Outlook | Google Agenda, Microsoft Outlook |
Why pick each one
Choose Claws Mail if…
- Released under the GPL-3.0 license
- Easy to set up — beginner-friendly
- Written in C
- Tiny footprint — runs in 128 MB RAM
Choose hash-calendar if…
- Released under the MIT license
- Written in JavaScript
- Lightweight — runs in 512 MB RAM
Frequently asked questions
Is Claws Mail or hash-calendar better?
Claws Mail is the stronger all-round pick: it has both the larger community and the simpler easy setup. Consider hash-calendar if its specific feature set fits your needs better.
Are Claws Mail and hash-calendar free and open-source?
Yes. Claws Mail is licensed under GPL-3.0 and hash-calendar under MIT. Both can be self-hosted at no software cost.
Can I run Claws Mail and hash-calendar with Docker?
Claws Mail: check the project docs for container support. hash-calendar: check the project docs for container support.