MDN’s new design is in Beta! A sneak peek:


This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The property RTCSessionDescription.sdp is a read-only DOMString containing the SDP which describes the session.


var value = sessionDescription.sdp;
sessionDescription.sdp = value; 


The value is a DOMString containing an SDP message like this one:

 o=alice 2890844526 2890844526 IN IP4
 c=IN IP4
 t=0 0
 m=audio 49170 RTP/AVP 0
 a=rtpmap:0 PCMU/8000
 m=video 51372 RTP/AVP 31
 a=rtpmap:31 H261/90000
 m=video 53000 RTP/AVP 32
 a=rtpmap:32 MPV/90000


// The remote description has been set previously on pc, an RTCPeerConnection



Specification Status Comment
WebRTC 1.0: Real-time Communication Between Browser
The definition of 'RTCSessionDescription.sdp' in that specification.
Working Draft Initial specification.

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) [1] (Yes) (Yes) [1] No support (Yes) ?
Feature Android Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? ? (Yes) ? No support ? ?

[1] Though this property is not prefixed, the interface it belongs to is.

See also

  • WebRTC
  • The standard for using SDP in an offer/answer protocol RFC 3264.

Document Tags and Contributors

 Contributors to this page: abbycar, Sheppy, teoli
 Last updated by: abbycar,