This feature has been removed from the Web standards. Though some browsers may still support it, it is in the process of being dropped. Avoid using it and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The RTCSessionDescriptionCallback type is used to represent the callback function passed into the deprecated callback-based version of createOffer() or createAnswer() when using them to create offers or answers.

Because this function type is part of the legacy WebRTC API, you should avoid using it (and the callback-based forms of createOffer() and createAnswer() that make use of it).




An RTCSessionDescriptionInit (or RTCSessionDescription) object describing the session being offered or being accepted. This object contains the type and sdp properties which are part of RTCSessionDescription.

Return value

The callback doesn't need to return anything, so the return value is undefined.


var pc = new RTCPeerConnection();
var descriptionCallback = function(offer) {


Specification Status Comment
WebRTC 1.0: Real-time Communication Between Browsers
The definition of 'RTCSessionDescriptionCallback' in that specification.
Candidate Recommendation Initial definition.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support Yes Yes22 ? ? ?
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes Yes Yes24 ? ? Yes

See also

Document Tags and Contributors

Contributors to this page: fscholz, Sheppy, tocretpa, teoli, wesj
Last updated by: fscholz,