khal vs Decsync Calendar Sync

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?
FeaturekhalDecsync Calendar Sync
Deploy effortRead-the-docs projectRead-the-docs project
Health score69 · Good15 · At risk
CategoryCalendar & ContactsCalendar & Contacts
LicenseMITGPL-3.0
LanguagePythonKotlin
Setup difficultyMediumMedium
Min. RAM64 MB128 MB
Deploymentbinary, sourcesource, binary
GitHub stars★ 3,054★ 699
First released20132018
ReplacesGoogle CalendarGoogle Calendar

What are khal and Decsync Calendar Sync?

khal

khal is a standards-based command-line calendar program that reads and writes iCalendar files and works with vdirsyncer to synchronize against self-hosted CalDAV servers. It offers an interactive console interface.

  • Command-line CalDAV calendar
  • Works with vdirsyncer
  • Interactive console interface

Decsync Calendar Sync

Decsync is a method and toolset for synchronizing calendars and contacts via a shared folder rather than a central server. Self-hosters pair it with a file-sync service to keep events consistent across devices.

  • Folder-based sync
  • No central server
  • Calendar and contacts
  • Pairs with any file sync

khal vs Decsync Calendar Sync: key differences

Khal is written in Python, while Decsync Calendar Sync is built with Kotlin. Licensing differs — MIT for khal versus GPL-3.0 for Decsync Calendar Sync. Khal is the lighter option, starting around 64 MB of RAM against 128 MB for Decsync Calendar Sync. Khal is the more established project (first released 2013), while Decsync Calendar Sync arrived in 2018. Khal has the considerably larger community, at 3,054 GitHub stars versus 699.

Why pick each one

Choose khal if…

  • Released under the MIT license
  • Active community (3.1k GitHub stars)
  • Written in Python
  • Tiny footprint — runs in 64 MB RAM
khal details

Choose Decsync Calendar Sync if…

  • Server-free architecture
  • Privacy friendly

Watch out for

  • Requires a sync layer
  • Setup is non-trivial
Decsync Calendar Sync details

Frequently asked questions

Is khal or Decsync Calendar Sync better?

Neither is universally better. khal has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.

Are khal and Decsync Calendar Sync free and open-source?

Yes. khal is licensed under MIT and Decsync Calendar Sync under GPL-3.0. Both can be self-hosted at no software cost.

Can I run khal and Decsync Calendar Sync with Docker?

khal: check the project docs for container support. Decsync Calendar Sync: check the project docs for container support.

Which is lighter on resources, khal or Decsync Calendar Sync?

khal has the smaller minimum footprint at 64 MB of RAM, compared to about 128 MB for Decsync Calendar Sync. Real-world usage depends on library size, user count, and enabled features.

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