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Home/Categories/Business & Productivity/Cal.diy
Cal.diy icon

Cal.diy

Open source alternative to Calendly, Acuity Scheduling and SimplyBook.me

  • 49.2K stars
  • MIT
  • Active this week
  • Last commit 2 days ago

Last verified Oct 20, 2026

Cal.diy is the MIT-licensed community edition of Cal.com for self-hosted scheduling, built for teams that want control without hosted Cal.com enterprise features.

Visit websiteGitHub49.2K starsDeploy on Hostinger
Cal.diy scheduling interface
TL;DR

Cal.diy is the MIT-licensed community edition of Cal.com for self-hosters who want Calendly-style booking pages and developer-controlled scheduling. It is not the hosted or enterprise Cal.com product, and the upstream README recommends self-hosting mainly for personal, non-production use unless you can operate the infrastructure yourself.

Read the full breakdownHide the full breakdownWho it is for, how it works, trade-offs and the FAQ
who it's for

Who Cal.diy is for#

Self-hosters controlling booking data

Use Cal.diy when you want to run booking pages and scheduling flows on infrastructure you operate.

Skip if:

Skip it if you need a supported managed scheduling service.

Developers evaluating scheduling infrastructure

Cal.diy fits teams that want source access before adapting scheduling behavior or embedding booking workflows into their own product.

Skip if:

Skip it if a simple hosted booking link is enough.

the problem

The problem it solves#

Hosted scheduling products are quick to adopt, but they can become limiting when booking flows need source access, data control, custom deployment choices, or product-level integration. Cal.diy gives self-hosters a Cal.com-derived codebase for running scheduling on their own infrastructure while keeping commercial Cal.com features out of the open-source claim.

how Cal.diy solves it

How it solves it#

Booking pages and routing

Cal.diy provides Calendly-style booking pages, availability rules, and scheduling flows that self-hosters can run from their own stack.

Developer-controlled codebase

The MIT repository gives teams source access for adapting booking behavior, integrations, and deployment details.

Community self-host path

Cal.diy removes Cal.com enterprise and hosted-product code so the listing points at the community edition, not commercial Cal.com.

strengths · trade-offs

Strengths and trade-offs#

Strengths

  • Clear MIT source evidenceThe canonical Cal.diy repository reports MIT licensing and is the source OSA should cite for this listing.
  • Good fit for self-hostersCal.diy is useful when scheduling data, deployment choices, and customization need to stay close to your own infrastructure.

Trade-offs

  • -Self-hosting burden is realThe upstream README warns that Cal.diy self-hosting needs server, database, and security knowledge and is mainly recommended for personal, non-production use.
  • -Not hosted Cal.comCommercial and enterprise-ready scheduling remains a Cal.com hosted or on-prem path, not a Cal.diy community-edition claim.
versus alternatives

Cal.diy vs alternatives#

Cal.diy vs Calendly

Cal.diy is a stronger fit when scheduling needs source access, self-hosting, and developer-controlled deployment. Calendly is a better fit for teams that only want a managed booking page with minimal setup. Choose Cal.diy when operating the scheduling stack yourself is worth the control; choose a hosted tool when speed and vendor support matter more than source ownership.

tech stack · detected from GitHub

What it's built on#

Languages
TypeScript
Frameworks
Next.jsReactTailwind CSS
Databases
PostgreSQL
Tooling
Turborepo
frequently asked

FAQ#

Is Cal.diy the same as Cal.com?

No. Cal.diy is the MIT-licensed community edition for self-hosters. Commercial and enterprise Cal.com features are separate from this listing.

Can Cal.diy replace Calendly?

Cal.diy can replace Calendly-style booking pages when you are willing to operate the scheduling stack yourself. Calendly is simpler for hosted scheduling.

What license does Cal.diy use?

The canonical Cal.diy repository reports MIT licensing. Review the upstream repository before using it in production.

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Hostinger

Run Cal.diy on your own server

Self-host Cal.diy on a Hostinger VPS.

Deploy on Hostinger

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