RTCPeerConnection: localDescription property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.

The localDescription read-only property of the RTCPeerConnection interface returns an RTCSessionDescription describing the session for the local end of the connection. If it has not yet been set, this is null.

Syntax

js
const sessionDescription = peerConnection.localDescription

On a more fundamental level, the returned value is the value of RTCPeerConnection.pendingLocalDescription if that property isn't null; otherwise, the value of RTCPeerConnection.currentLocalDescription is returned. See Pending and current descriptions in the WebRTC Connectivity page for details on this algorithm and why it's used.

Example

This example looks at the localDescription and displays an alert containing the RTCSessionDescription object's type and sdp fields.

js
const pc = new RTCPeerConnection();
// ...
const sd = pc.localDescription;
if (sd) {
  alert(`Local session: type='${sd.type}'; sdp description='${sd.sdp}'`);
} else {
  alert("No local session yet.");
}

Specifications

Specification
WebRTC: Real-Time Communication in Browsers
# dom-peerconnection-localdescription

Browser compatibility

BCD tables only load in the browser

See also