API rate limiting

The Sitecore Send API enforces rate limiting to prevent the API from being overwhelmed by too many requests. This means that it allows only a certain number of API calls from users within a given time. If a user sends too many requests, API rate limiting can throttle client connections.

The following table describes the current rate limit (number of requests per 10 seconds) per user (per API key):

Resource	Method	Endpoint path	Rate limit
Campaign Statistics Activity	GET	/campaigns/{CampaignID}/stats/{Type}.{Format}	2 calls / 60s
Add subscribers	POST	/subscribers/{MailingListID}/subscribe.{Format}	10 calls / 10s
Add multiple subscribers	POST	/subscribers/{MailingListID}/subscribe_many.{Format}	2 calls / 10s
Unsubscribe a subscriber from an account	POST	/subscribers/unsubscribe.{Format}	20 calls / 10s
Unsubscribe a subscriber from an email list	POST	/subscribers/{MailingListID}/unsubscribe.{Format}	20 calls / 10s
Unsubscribe a subscriber from an email list and a campaign	POST	/subscribers/{MailingListID}/{CampaignID}/unsubscribe.{Format}	20 calls / 10s
Delete a subscriber	DELETE	/subscribers/{MailingListID}/delete.{Format}	40 calls / 10s
Delete multiple subscribers	DELETE	/subscribers/{MailingListID}/delete_many.{Format}	8 calls / 10s
Send a transactional campaign	POST	/campaigns/transactional/send.{Format}	6 calls / 1s
Manage a transactional campaign	POST	/campaigns/transactional/send.{format}	500

Example response

The following is an example of a response when request submissions exceed the rate limit. When you go over the rate limit, you receive a RATE_LIMITING error in the response body.

json

{
  "Code": 429,
  "Error": "RATE\_LIMITING",
  "Context": null
}

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