Rate Limits

The number of requests the API consumer can make in a second

A rate limit is the number of API requests (calls) an app or user can make within a defined time.

If the number of requests exceeds the limits described in the table below, requests are temporarily blocked (throttled) until the rate limit window resets; the responses return an error with status code 429.

The methods not listed in this table share a total default rate limit of 200 requests per second.

Events sent through the Generate event and Generate past events resources are processed asynchronously, and the processing order isn't guaranteed. Don't rely on the order in which requests are sent: for historical events, the reference point is the time passed in the event itself, in the occurred field.

MethodRequest typeEndpointMax requests per second
Get contact ID by tokenGET/api/v1/contact/token/{app_uuid}/{token_id}/contactId150
Search for contactsGET/api/v1/contacts50
Generate events v1POST/api/v1/event350
Generate past events V1POST/api/v1/past_events100
Delete eventsDELETE/api/v1/past_events5
Update interaction statusPUT/api/v1/interactions/{interaction_id}/status300
Get contact's message historyGET/api/v2/contacts/messages10
Generate event v2POST/api/v2/event350
Generate past events V2POST/api/v2/past_events100
Get email messageGET/api/v1/messages/email/{id}10
Generate event v3POST/api/v3/event350
Generate past events V3POST/api/v3/past_events100

Hourly limit on message retrieval requests

Requests to the /v1/messages resources — for example, Get Email message and Get Email message view link — are limited to 500 requests per hour by default. To increase the limit for your account, contact support.

Hourly limit on single email sends

In addition to the per-second request limits, each account has an hourly limit on single (one-off) email sends — 100 emails per hour by default. The limit applies to email messages sent by workflow message blocks and by the Send prepared message and Send Email message API resources. Bulk campaigns are not affected.

When the limit is exceeded, the API returns a 403 error Per hour emails limit reached: N, where N is the current limit value. The same error is displayed in the workflow launch history. Sends rejected over the limit fail and are not retried automatically.

To increase the limit for your account, contact support.