Cal.com

Open-source scheduling infrastructure — a self-hostable alternative to Calendly for booking meetings and appointments.

Open source alternative to:

Cal.com is an open-source scheduling platform that allows you to create personalized booking pages for meetings, consultations, and appointments. It integrates with your existing calendar (Google Calendar, Outlook, etc.) and lets others book available slots without the email back-and-forth.

Cal.com supports multiple event types, team scheduling with round-robin or collective availability, payment integration (Stripe), video conferencing (Zoom, Google Meet, Teams), webhooks, API access, and detailed analytics. It can be fully self-hosted, giving enterprises complete control over their scheduling data and customization.

As an open-source alternative to Calendly, Cal.com offers a comparable feature set with the added benefit of self-hosting. Organizations that handle sensitive client scheduling data — medical practices, legal firms, therapists — benefit from keeping that data on their own infrastructure. Cal.com is free to self-host and has a cloud-hosted version with a freemium model.