Zcal · Rate Limits

Zcal Rate Limits

Zcal does not publish a general-purpose public REST API, and as a result there is no documented inbound API rate-limit policy (RPM / TPM / quotas) to reconcile. The primary programmatic surface is OUTBOUND webhooks, where Zcal POSTs booking lifecycle events to a subscriber URL you control; in that direction your own endpoint is the receiver, so any throughput limits are governed by the volume of bookings rather than an API quota. No public webhook delivery rate limit, retry schedule, or concurrency limit is documented at the sources reviewed.

Zcal Rate Limits is the machine-readable rate-limit profile for Zcal on the APIs.io network, in the API Commons Rate Limits shape.

It captures 2 rate-limit definitions, measuring requests and events.

An exhausted limit returns HTTP not documented.

This profile was written by API Evangelist and has not been verified against a page the provider published; treat every limit as unconfirmed until a dated transcription replaces it.

The profile also includes 2 backoff/retry policies defined and response codes documented for throttled.

Tagged areas include Scheduling, Calendar, Booking, Meetings, and Webhooks.

2 Limits Exhausted: HTTP not documented
Method: generated, dated 2026-06-21.
Written by API Evangelist on 2026-06-21 and not verified against a page the provider published. Treat every limit as unconfirmed until a dated transcription replaces it.
View Source
SchedulingCalendarBookingMeetingsWebhooksRate LimitingQuotasThrottling

Limits

Inbound REST API Rate Limit account
requests
not applicable
No documented public REST API, so no inbound API rate limit exists.
Outbound Webhook Delivery subscription
events
not documented
Zcal POSTs event.created / event.rescheduled / event.cancelled to your subscriber URL. No delivery rate, retry policy, or concurrency limit is documented.

Policies

No Documented API Throttling
Because Zcal exposes no public inbound REST API, there is no published throttling or quota policy to enforce against.
Webhook Receiver Responsibility
Subscribers should return a fast 2xx and process payloads asynchronously; verify the optional x-zcal-webhook-signature HMAC SHA-256 header to authenticate deliveries.

Sources

Work with this as data

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Tools for rate limits

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