SHSelfHostIndex

Cal.diy vs ETAR

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?
CA Cal.diy Online appointment scheduling system VS ET ETAR Open-source calendar server companion for events
FeatureCal.diyETAR
CategoryCalendar & ContactsCalendar & Contacts
LicenseMITGPL-3.0
LanguageTypeScriptJava
Setup difficultyMediumMedium
Min. RAM512 MB256 MB
Deploymentbare-metaldocker, source
GitHub stars★ 47,334★ 2,565
First released20262016
Replaces—Google 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
Cal.diy details

Choose ETAR if…

  • Open ecosystem
  • No vendor lock-in
ETAR details

Frequently asked questions

Is Cal.diy or ETAR 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 ETAR free and open-source?

Yes. Cal.diy is licensed under MIT and ETAR under GPL-3.0. Both can be self-hosted at no software cost.

Can I run Cal.diy and ETAR with Docker?

Cal.diy: check the project docs for container support. ETAR: yes.

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