Quickstart

The Opencals Storefront API is a REST booking API for developers. It exposes everything a booking website needs — services, real-time availability, staff members, locations, carts, checkout, and payments — so you can build a fully custom booking experience on any stack while Opencals handles scheduling logic, conflict prevention, and order management behind the scenes. Every screen in the Opencals dashboard has a programmatic equivalent. If you can configure it in Opencals, you can read it over the API.

Base URL

All Storefront API endpoints live under a single base URL:

https://api.opencals.com

Endpoint paths are prefixed with /storefront — for example GET /storefront/products lists your bookable services. Responses are JSON with camelCase property names.

Make your first request

Get an API key

Sign up at opencals.com and set up your store — services, staff members, locations, and schedules.
In the dashboard, go to Settings → API Keys and create a new Storefront API Key.
Each key is scoped to your store and starts with sfk_.

Keep the key server-side (for example in an environment variable). It identifies your store and should never be shipped to the browser.

List your services

List your store’s active services with a single call:

curl "https://api.opencals.com/storefront/products" \
  -H "X-Api-Key: sfk_your_key_here"

Read the response

The response is a paginated collection:

{
  "data": [
    {
      "id": "9c6f7c2e-…",
      "title": "Haircut",
      "duration": 3600,
      "price": 4500,
      "maxAttendees": 1
    }
  ],
  "meta": {
    "page": 1,
    "take": 50,
    "itemCount": 12,
    "pageCount": 1,
    "hasPreviousPage": false,
    "hasNextPage": false
  }
}

You can also try every endpoint directly in the interactive API reference.

Pagination

List endpoints accept page (1-indexed) and take (items per page, maximum 100) query parameters and return a meta object with page, take, itemCount, pageCount, hasPreviousPage, and hasNextPage.

curl "https://api.opencals.com/storefront/products" \
  -H "X-Api-Key: sfk_your_key_here" \
  --url-query "page=2" \
  --url-query "take=20"

Rate limits

Requests are rate-limited per API key:

Category	Limit
General	100 requests / 60 seconds
Authentication	20 requests / 10 seconds
Password reset	5 requests / hour
Registration	10 requests / minute

When you exceed a limit the API responds with 429 Too Many Requests.

Timezones

All date and time values in requests and responses are in UTC. Availability endpoints accept a timezone query parameter (for example America/New_York) so slots come back converted for display, and you should convert user-selected times back to UTC before creating appointments.

Next steps

Authentication

API keys, customer tokens, and error responses.

Build a booking page

The full flow from listing services to a confirmed booking.

Storefront SDK

The typed TypeScript client for this API.

API reference

Every endpoint, parameter, and response shape.

Get started

Guides

Base URL

Make your first request

Rate limits

Timezones

Next steps

Authentication

Build a booking page

Storefront SDK

API reference

​Base URL

​Make your first request

​Pagination

​Rate limits

​Timezones

​Next steps

Authentication

Build a booking page

Storefront SDK

API reference

Base URL

Make your first request

Pagination

Rate limits

Timezones

Next steps