Webhook events

Webhooks let your application react to Cal ID activity in real time. You register a subscriber URL and choose which events to receive; Cal ID then sends an HTTP POST with a JSON payload each time one of those events occurs. Create a subscription with the Create a webhook endpoint:

curl -X POST https://api.cal.id/webhook/ \
  -H "Authorization: Bearer calid_xxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "subscriberUrl": "https://example.com/webhooks/calid",
    "eventTriggers": ["BOOKING_CREATED", "BOOKING_CANCELLED"],
    "secret": "whsec_your_secret"
  }'

string

required

The URL that receives the webhook POST requests.

string[]

required

The events to subscribe to — one or more of the triggers below.

string

Optional shared secret used to sign each payload so you can verify it’s genuinely from Cal ID.

string

Optional custom template for the payload delivered to your subscriber URL.

You can manage subscriptions with the List, Get, Update, and Delete webhook endpoints, or from the Cal ID dashboard.

Event triggers

Trigger	Fires when
`BOOKING_CREATED`	a booking is confirmed
`BOOKING_REQUESTED`	a booking that requires confirmation is requested
`BOOKING_RESCHEDULED`	a booking is moved to a new time
`BOOKING_CANCELLED`	a booking is cancelled
`BOOKING_REJECTED`	a booking request is declined
`BOOKING_PAYMENT_INITIATED`	payment for a paid booking begins
`BOOKING_PAID`	a paid booking is successfully paid
`BOOKING_NO_SHOW_UPDATED`	an attendee is marked as a no-show
`FORM_SUBMITTED`	a routing form is submitted
`OOO_CREATED`	an out-of-office entry is created

Payload

Each delivery is a JSON body containing the trigger, a timestamp, and the event payload:

{
  "triggerEvent": "BOOKING_CREATED",
  "createdAt": "2026-01-14T09:30:00.000Z",
  "payload": {
    "title": "30 Min Meeting between Alex and John Doe",
    "startTime": "2026-01-15T09:30:00Z",
    "endTime": "2026-01-15T10:00:00Z",
    "organizer": {
      "name": "Alex",
      "email": "alex@example.com",
      "timeZone": "Asia/Kolkata"
    },
    "attendees": [
      {
        "name": "John Doe",
        "email": "john@example.com",
        "timeZone": "Asia/Kolkata"
      }
    ],
    "eventTypeId": 42,
    "uid": "bk_1234567890"
  }
}

The exact fields in payload vary by event. If you set a payloadTemplate when creating the webhook, Cal ID delivers that template instead.

Verify deliveries

If you set a secret, use it to confirm each incoming request is authentic and hasn’t been tampered with before you act on it. Reject any request whose signature doesn’t match. Respond with a 2xx status quickly — do the heavy work asynchronously so deliveries aren’t retried unnecessarily.

Webhooks in the dashboard

Prefer a no-code setup? Create and manage webhooks from Settings → Webhooks in Cal ID.

Get started

Endpoints

Webhook events

Event triggers

Payload

Verify deliveries

Webhooks in the dashboard

​Subscribe to events

​Event triggers

​Payload

​Verify deliveries

Webhooks in the dashboard

Subscribe to events

Event triggers

Payload

Verify deliveries