Cal.com API
Cal.com's open-source scheduling API for managing availability, event types, bookings, and calendar integrations — available as cloud or self-hosted.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
Open-source scheduling platform. API key auth. Meeting attendee data is PII. Self-hostable for full privacy control. OAuth2 for user-scoped access.
⚡ Reliability
Best When
An agent needs full API control over scheduling including creating event types, or when self-hosting is required for data privacy.
Avoid When
You need a no-code scheduling solution or are looking for Calendly's specific integrations.
Use Cases
- • Creating and managing event types and booking pages programmatically
- • Reading and managing bookings for automated workflows
- • Setting availability schedules for teams and individuals
- • Building custom scheduling interfaces with full API control
- • Self-hosted scheduling with data residency requirements
Not For
- • Teams needing Calendly's polished UI without development effort
- • Very simple one-person scheduling without API needs
- • Teams without technical resources for self-hosting (use cloud instead)
Interface
Authentication
API keys for personal access (v1). OAuth2 for platform integrations (v2). v2 API uses OAuth tokens. Both versions coexist — verify which version is needed.
Pricing
Free cloud tier is very generous. Self-hosting is completely free. API access on all tiers. Much better free tier than Calendly for API users.
Agent Metadata
Known Gotchas
- ⚠ Two API versions (v1, v2) with different auth and capabilities — documentation can be confusing
- ⚠ Self-hosted deployments require maintaining your own infrastructure and SSL
- ⚠ Webhook events have evolved between versions — check event types carefully
- ⚠ Rate limits not publicly documented — agents may hit undocumented limits
- ⚠ Calendar integration (Google, Outlook) must be set up by end user, not API
- ⚠ Booking reschedule logic requires creating new booking then canceling old one
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Cal.com API.
Scores are editorial opinions as of 2026-03-06.