What is the message delivery volume/ minute, speed of delivery for sending bulk messages with WhatsApp Business API?

In general, the WhatsApp channel of the Conversation API allows you to send up to 65 messages per second. Burst capacity (where the throughput temporarily exceeds the sustained throughput rating) is also available, and messages which hit that burst capacity will be queued for send. This really only becomes an issue when you have particularly time sensitive content, for example, OTP.

Note: In addition to the rate limitations applied by the WhatsApp channel itself, there are Conversation API project and app rate limitations to consider as well. Sinch can offer higher throughput APIs at additional cost. Please contact your Sinch account manager for more information.

Learn more about the Sinch WhatsApp Business API.