AddCal

Powerful Calendar API

Create and manage calendar events programmatically with our modern, RESTful API. Built for developers, with comprehensive documentation and examples.

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Why Developers Love Our API

Simple Event Creation

Create calendar events with minimal data. Smart defaults handle the rest.

POST /api/events { "title": "Team Meeting", "start": "2024-01-15T14:00:00Z" }
Automatically creates calendars, handles timezones, and sets durations

RESTful Design

Clean, predictable endpoints following REST conventions.

GET /api/calendars/{id}/events POST /api/calendars/{id}/events DELETE /api/events/{id}
Intuitive resource structure with proper HTTP methods

Smart Automation

Webhook-driven event creation without manual intervention.

POST /s/{smart-link-key} title=Contact+Form+Submission start=2024-01-15T14:00:00Z
Perfect for contact forms, CRM integrations, and workflows

Smart Links

Smart Links are dynamic automation workflows that create events based on external triggers. They're perfect for integrating with forms, webhooks, and other services.

Key Features

  • Create events from webhook triggers
  • Automatic approval workflows
  • HMAC signature verification for security
  • Integration with Zapier and other platforms
  • Event status tracking (pending, approved, rejected)

Common Use Cases

  • Contact form submissions that create calendar events
  • Meeting requests from external systems
  • Automated scheduling workflows
  • Event registration systems
Learn More About Smart Links

API Features

Simple Event Creation

Create events with smart defaults and automatic calendar management

  • Automatic 1-hour duration if no end time specified
  • Flexible calendar selection and creation
  • Timezone inheritance from calendar
  • Support for all-day events

Calendar Management

Organize events into calendars with team support

  • Create and manage multiple calendars
  • Team-based access control
  • Calendar subscription endpoints
  • Detailed analytics and insights

Frequently Asked Questions

Do I need authentication to use the API?

Yes, most endpoints require authentication using a Bearer token. You can get your API token from your user settings. However, the Calndr.link compatibility endpoints are public and do not require authentication.

What response format does the API use?

All API responses are in JSON format and follow a consistent structure. The response includes the data object containing the requested resource, and for event endpoints, additional links for various calendar platforms.

Are there any rate limits?

Yes, API requests are rate-limited to ensure fair usage. The specific limits depend on your account type. Contact us if you need higher limits.

How do I handle timezones?

The API accepts timezone strings (e.g., "America/New_York") and handles all datetime conversions. You can specify a timezone per event, or it will inherit from the calendar settings.