Currently our platform does not limit the number of participants in a session unless a limit is specifically set via the API for a given AppKey. In the case of the client, assuming adequate available bandwidth, the maximum number of participants will typically be limited by the CPU/GPU capacity of the client. In the case of a fairly recent mid-range desktop or laptop computer 6-8 users with both audio and video enabled is a reasonable expectation. This number will be higher when using a signalling only or audio only call.
With the Skylink MCU feature, this number can increase (Learn more about our MCU/SFU).
On mobile devices CPU, availability of hardware acceleration, battery life, and available bandwidth are the primary limitations. On a recent mid-to-high-end Android or iOS device, 4 participants is a reasonable expectation on a 4G/LTE network. It should be noted that multi-party calls can have significant impact on battery life.