Overview

Rate Limits

Understanding Calendly API rate limits and best practices

Calendly’s API uses user-based rate limiting to ensure service quality, system stability, and fair usage across customers.

Current Rate Limits

Billing TierRate Limit
Paid Plans500 requests per user per minute
Free Plan50 requests per user per minute
  • These limits apply to both direct API calls and calls made through third-party integrations.
  • Rate limits are enforced per user.
  • Only 8 OAuth tokens per user can be requested within a span of 1 minute.

Endpoint Specific Rate Limits

EndpointBilling TierRate Limit
Create Event InviteeTrial5 requests per user per day
Create Event InviteePaid, Non-Enterprise10 requests per user per minute
Create Event InviteePaid, Non-Enterprise50 requests per user per hour
Create Event InviteePaid, Non-Enterprise100 requests per user per day
Create Event InviteeEnterprise500 requests per user per minute

Behavior When Rate Limits Are Exceeded

If you exceed your allowed rate limit, the Calendly API will respond with:

1HTTP/2 429 Too Many Requests
2Date: Wed, 10 Jan 2024 12:00:00 GMT
3Content-Type: application/json
4X-RateLimit-Limit: {your limit}
5X-RateLimit-Remaining: 0
6X-RateLimit-Reset: 60

All responses include the following headers:

HeaderDescription
X-RateLimit-LimitYour rate limit ceiling
X-RateLimit-RemainingNumber of requests left in the current window
X-RateLimit-ResetNumber of seconds until the limit resets (typically 60 seconds)

Best Practices

  • Use the X-RateLimit-Remaining and X-RateLimit-Reset headers to monitor and manage your API usage.
  • If you receive a 429 response, wait until the X-RateLimit-Reset time has elapsed before retrying.
  • Implement exponential backoff or retry-after logic to gracefully handle retries.