Calendr API
Calendr API for teams that need scheduling automation beyond the dashboard
The Calendr API connects your firm's booking pages, contacts, and reporting data to the tools you already run — so ops teams and developers can automate availability checks, bookings, and follow-up without copying details between systems by hand.
The operating problem
Booking workflows break when scheduling data is trapped in the UI
Growing teams eventually need more than manual dashboard work: syncing a booked meeting into an internal tool, checking whether a rep has onboarding slots left, renaming an organisation after CRM cleanup, or exporting booking counts for a weekly ops review.
The Calendr API exposes those jobs as firm-scoped HTTP endpoints. Client-facing booking still happens through branded booking pages, round robin, and multi-host booking — the API is for the automation layer behind them.
API surface
What you can access through API v1
All endpoints are firm-scoped, return JSON, and use Calendr hash IDs in responses.
Scheduling
- List event types and read availability for a date and timezone
- Create, fetch, cancel, and reschedule bookings
CRM records
- Search, create, update, and delete organisations and people
- List and update contact cards linked to people and organisations
Forms and team management
- Read qualifying form and booking form submissions
- List team members, invite users, archive colleagues, and restore users (admin)
Reporting
- Booking summary counts for a date range
- Breakdowns by team member or event type
Pairs with booking reports in the app when you want charts and saved views for managers.
Authentication
Bearer tokens with firm-scoped permissions
Firm admins generate API tokens in Settings → Integrations. Each token inherits the creating user's permissions, so a standard user's token cannot perform admin-only actions such as inviting colleagues or deleting contacts.
Destructive requests require explicit confirmation parameters, and write actions are recorded in the API audit log so admins can see what automation changed.
Quick start
GET https://calendr.so/api/v1/event_types
Authorization: Bearer cal_...
Accept: application/json
Base URL: https://calendr.so/api/v1.
API access is included in the calendr.so plan — no separate developer tier.
Works with calendr.so
API automation alongside the rest of the scheduling stack
Native integrations such as Notion and Karbon handle common CRM workflows out of the box. The API is for the custom layer — internal tools, bespoke routing, or data exports your team still maintains itself.
Prefer AI assistants over raw HTTP? The Calendr MCP server calls the same API v1 endpoints from Cursor, Claude Desktop, and other MCP-compatible clients — so you can use the AI stack you already pay for without a bundled AI surcharge on scheduling.
See the full integrations overview for calendar, CRM, API, and MCP connections.
Getting started
Generate a token and call your first endpoint
Start a trial, create an API token as a firm admin, then call /api/v1/event_types to confirm authentication.
Connect Calendr MCP
Step-by-step token setup, MCP configuration, and examples for Cursor and Claude Desktop using the same API credentials.
Read the setup guide →
Pricing
One plan includes API access, team scheduling, booking forms, calendar sync, reporting, and MCP — with no feature tiers or AI bundle markup.
See pricing →
Frequently asked questions
- What is the Calendr API?
- The Calendr API is a firm-scoped JSON API at https://calendr.so/api/v1. It lets developers and ops teams automate scheduling workflows — checking availability, creating or rescheduling bookings, updating contacts, reading form submissions, and pulling booking reports.
- How do I authenticate with the Calendr API?
- Create a bearer token in calendr.so under Settings → Integrations → Generate API token. Send it on every request as Authorization: Bearer cal_.... Tokens inherit the permissions of the user who created them.
- Is API access included in my calendr.so subscription?
- Yes. API access is included in the one calendr.so plan. There is no separate developer tier or per-endpoint add-on.
- What can I automate with the Calendr API?
- Common uses include internal booking tools, ops scripts, CRM glue, reporting exports, and custom workflows around event types, organisations, people, contact cards, bookings, qualifying form submissions, booking form submissions, team invitations, and booking summary or breakdown reports.
- How is the Calendr API different from the MCP server?
- The API is for direct HTTP integrations and custom code. The MCP server wraps the same API v1 endpoints for AI assistants such as Cursor and Claude Desktop. Use the API when you are building your own integration; use MCP when you want an assistant to call Calendr tools from chat.
- Do admin-only API actions require an admin token?
- Yes. Actions such as deleting contacts, inviting users, and archiving colleagues require a token created by a firm admin. Other endpoints follow the creating user's normal calendr.so permissions.
- Are there rate limits on the Calendr API?
- Yes. The API applies per-token limits, including 120 requests per minute, tighter limits on destructive actions, and invitation throttling. Write actions are recorded in the API audit log.
Automate calendr.so with the API included in your plan
Start your 14-day free trial, generate a firm API token, and connect scheduling data to the tools your team already runs.
No credit card required