Cal.com — Open-source scheduling you control

Ever lost time juggling calendars, link replies, and timezone math for meetings? Scheduling tools promise simplicity, but many lock you into proprietary platforms and obscure your data. What if you could run a polished, customizable scheduler on your own domain — with full access to the code and integrations?

Cal.com is that answer: a mature, open-source scheduling platform (a Calendly successor) that you can self-host or use via cal.com. Built for teams and developers, it combines rich integrations, a flexible API, and a developer-friendly stack so you own your scheduling experience and data.

What It Does

Cal.com provides scheduling infrastructure for individuals and teams. At its core it:

Publishes bookable pages (individuals, teams, and organization profiles).
Handles availability, conflict detection, timezones, and bookings.
Integrates with calendars (Google, Office 365), video providers (Zoom, Daily), CRMs (HubSpot, Pipedrive), and messaging providers (Twilio, SendGrid).
Supports self-hosting, white-labeling, and API-driven workflows for deep customization.

Key point: Cal.com is API-first, extensible, and designed so you can run it on your own infrastructure — keeping control of your data and workflows.

Who It’s For

Cal.com targets a broad audience:

Developers who want an extendable scheduling system built with Next.js, tRPC, Prisma and TypeScript.
Startups & SMBs that want a white-label booking site or to self-host to comply with privacy/regulatory needs.
Enterprise teams that need advanced workflows, multi-tenant organizations, SSO and commercial support (available via the EE packages).
Non-technical admins who benefit from easy deployment options like Vercel, Render, Railway or Docker templates.

How It Works

Cal.com is a full-stack TypeScript monorepo. High-level architecture:

Frontend: Next.js + React with Tailwind CSS for UI and embed/booker components.
API layer: tRPC-powered endpoints that serve the dashboard and public booking pages.
Database: PostgreSQL (Prisma ORM is used for schema & migrations).
Integrations: Connectors for Google Calendar, Office365, Zoom, Daily, and other providers using OAuth and service credentials.
Deployment: Deployable via Docker, Vercel, Railway, Render or cloud providers; repo includes deployment guides and a docker repository.

Notable design choices

Monorepo with packages for atoms (UI), platform libraries, and platform-specific features.
Open-core licensing: the majority is AGPLv3 open-source while enterprise features live under a commercial EE package.
Feature flagging and extensibility to enable self-hosted or managed usage.

Getting Started

Below are concise steps to run a local development instance. For full details and advanced deployment, see the project GitHub repo and official docs on cal.com.

Quick setup

<!-- Clone the repository -->
  git clone https://github.com/calcom/cal.com.git
  cd cal.com

  <!-- Install dependencies (Yarn recommended) -->
  yarn

  <!-- Copy example env and generate secrets -->
  cp .env.example .env
  # generate NEXTAUTH_SECRET and CALENDSO_ENCRYPTION_KEY
  openssl rand -base64 32  # copy into .env as NEXTAUTH_SECRET and CALENDSO_ENCRYPTION_KEY

  <!-- Start a local Postgres DB (or use Docker / Railway) -->
  # using Prisma migrations in dev
  yarn workspace @calcom/prisma db-migrate

  <!-- Development server -->
  yarn dev

Quick Docker-based start (recommended for dx)


  # Requires Docker & Docker Compose
  yarn dx

If you plan to deploy to production, the repo includes deployment guides for AWS, GCP and Azure plus templates for Vercel / Render / Railway and a community-maintained Docker repo.

Key Features

Self-host or managed — run on your domain or use the hosted Cal.com.
White-label & branding — control appearance and domain for booking pages.
Integrations — Google Calendar, Office365, Zoom, Daily, HubSpot, Twilio, SendGrid and many more via App Store packages.
Round-robin & teams — team scheduling and assignment rules for fair distribution.
Platform & API — tRPC APIs and webhooks for deep automation and custom workflows.
Localization — translations and community contributions for many languages.
Extensible UI atoms — atomic UI components that teams can reuse or override.

Why It’s Worth Trying

Cal.com blends production-ready features with an open, community-driven model:

Community & momentum: the project has tens of thousands of stars and a large contributor base — a sign of active development and ecosystem integrations.
Flexible hosting: pick managed hosting for convenience or self-host to meet compliance and customization needs.
Enterprise path: if you need SSO, admin panels, or advanced enterprise features there is an EE offering supported by the core team.
Real-world use: used for business meetings, webinars, classes, and large organizations needing team scheduling rules and delegation credentials for domain-wide calendar setups.

Community snapshot: the repository has over 36k stars, ~9.7k forks, and contributions from hundreds of contributors. Releases are frequent and the project maintains an active changelog and release cadence.

Where to Learn More

GitHub — calcom/cal.com (source code, issues, pull requests, releases)
Cal.com official site (product pages, hosted plans and roadmap)
Roadmap — see planned features and priorities
Docs and integration guides (Google, Microsoft, Zoom, Daily) are linked from the repo README and the docs site.

Final thought: if you need control, extensibility, and an active community, Cal.com is a compelling option — whether you want to embed a simple booker widget or build a full scheduling platform that runs on your infrastructure.

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