Knowledge
The open source Calendly alternative. Self host it, or have it hosted. Integrate it seamlessly into your business with advanced customization and an open API.
| What is it | The open source Calendly alternative. Self host it, or have it hosted. Integrate it seamlessly into your business with advanced customization and an open API. |
|---|---|
| Pricing | Paid — from $15/mo |
| Free tier | Yes |
| Platform | Web Application |
| API | Yes |
| Works with | IFTTT, Make, n8n, Zapier |
| Best for | booking client meetings, scheduling job interviews |
| Domain registered | 1997 |
Data updated Aug. 1, 2026
What does Knowledge do?
Cal.com is an open-source scheduling platform that eliminates the back-and-forth of meeting coordination. It connects directly to your Google, Outlook, or Apple calendar, automatically checking your availability and preventing double-bookings. You create personalized booking pages with your available time slots, then share a link that lets others book meetings directly based on your real-time availability.
The platform stands out with its developer-friendly approach and extensive customization options. It offers robust API access, white-labeling capabilities, and over 50 integrations with video conferencing tools like Zoom, Google Meet, and Microsoft Teams. The self-hostable open-source version gives organizations full control over their scheduling infrastructure, while the cloud version provides a streamlined SaaS experience.
This tool benefits professionals who schedule frequent meetings—sales teams booking demos, recruiters coordinating interviews, consultants managing client calls, and educators arranging office hours. Teams particularly benefit from collaborative features like round-robin scheduling and collective availability views, making it ideal for businesses scaling their scheduling operations.
Key features
What makes it stand outWho is Knowledge for?
Who benefits most from this toolPricing
Free tier available — start without a credit cardFree
- 1 user
- Unlimited calendars
- Unlimited event types
- Workflows
- Integrate with your favorite apps
- Accept payments via Stripe
- HTML & React Embed
- Cal.ai phone agent
- Cal Video
Teams
Everything in Free, plus:
- 750 credits per user
- 1 team
- Schedule meetings as a team
- Round-robin, fixed round-robin
- Collective events
- Routing forms
- Teams workflows
- Insights - analyze your booking data
- Remove branding
- Same day email and chat support
Organizations
Everything in Teams, plus:
- 1,000 credits per user
- 1 parent team and unlimited sub-teams
- Organization workflows
- Yourcompany.cal.com subdomain
- SOC2, HIPAA, ISO 27001 compliance check
- SAML SSO and SCIM
- Cal.com instant meetings
- Domain-wide delegation
- Member attributes
- Attribute-based routing
- Extensive whitelabeling
- Priority email and chat support
Enterprise
Everything in Organizations, plus:
- Dedicated Database
- Active directory sync
- Sync your HRIS tools
- Advanced routing
- Dedicated onboarding and engineering support
- Enterprise-level support
- 99.9% uptime SLA
- 24/7 real-time Slack Connect and phone support
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