Cal.diy vs Crab Fit

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?
FeatureCal.diyCrab Fit
Deploy effortRead-the-docs projectUnder-an-hour setup
Health score96 · Excellent58 · Fair
CategoryCalendar & ContactsCalendar & Contacts
LicenseMITMIT
LanguageTypeScriptTypeScript
Setup difficultyMediumEasy
Min. RAM512 MB256 MB
Deploymentbare-metaldocker
GitHub stars★ 48,631★ 531
First releasedNone2020
ReplacesCalendly, DoodleWhen2meet, Doodle

What are Cal.diy and Crab Fit?

Cal.diy

Scheduling infrastructure for absolutely everyone.

  • Self-hosted appointment scheduling
  • Calendar and video integrations
  • Team and round-robin booking
  • Webhooks and API

Read the full Cal.diy guide →

Crab Fit

Crab Fit is an open-source scheduling tool that helps groups find a time to meet by overlaying everyone's availability. Participants mark free slots without registering, and a heatmap reveals the best overlap, similar to When2meet.

  • Availability heatmap
  • No registration required
  • Group time-finding

Cal.diy vs Crab Fit: key differences

Both projects are written in TypeScript. Crab Fit is the lighter option, starting around 256 MB of RAM against 512 MB for Cal.diy. Cal.diy has the considerably larger community, at 48,631 GitHub stars versus 531. Crab Fit lists first-class Docker deployment; Cal.diy does not.

Why pick each one

Choose Cal.diy if…

  • Permissive MIT license
  • Flexible scheduling workflows
  • Multi-user support

Watch out for

  • Setup can be involved
  • Younger than established rivals
Cal.diy details

Choose Crab Fit if…

  • Released under the MIT license
  • Easy to set up — beginner-friendly
  • First-class Docker support for quick deployment
  • Written in TypeScript
Crab Fit details

Frequently asked questions

Is Cal.diy or Crab Fit better?

Neither is universally better. Cal.diy has the larger community, while Crab Fit is simpler to set up (easy difficulty). Choose based on the comparison table above and your own setup.

Are Cal.diy and Crab Fit free and open-source?

Yes. Cal.diy is licensed under MIT and Crab Fit under MIT. Both can be self-hosted at no software cost.

Can I run Cal.diy and Crab Fit with Docker?

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

Which is lighter on resources, Cal.diy or Crab Fit?

Crab Fit has the smaller minimum footprint at 256 MB of RAM, compared to about 512 MB for Cal.diy. Real-world usage depends on library size, user count, and enabled features.

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