The kind property of the RTCRtpStreamStats dictionary is a string indicating whether the described RTP stream contains audio or video media.

Its value is always either "audio" or "video".

This property was previously called mediaType. The name was changed in the specification in February, 2018. See Browser compatibility below to determine how this affects the browsers you're targeting.

A string whose value is "audio" if the track whose statistics are given by the RTCRtpStreamStats object contains audio, or "video" if the track contains video media.

This string will always be the same as the one provided by the associated MediaStreamTrack object's kind property. It will also match the statistics object's RTCCodecStats.codec property's media type.