Rate limiting is imposed on each available API endpoint and will return the appropriate HTTPS error codes (e.g.,
503, etc.) depending on the state of the system.
Two forms of rate limiting are currently supported:
429error code. The current rate limits for the endpoints are 20 requests per second, with bursts allowed up to 60 requests per second.
When you hit either of these rate limiting scenarios, what you should do is halt any further requests and slow down the pace of API requests. If you start seeing many rate limit errors, it would be advisable to build a queue on your end to throttle the requests.
If your expected average send-rates are significantly higher and queuing is not an effective strategy, please look into our High Availability and Scaling options.