RTCPeerConnection.iceConnectionState

The read-only property RTCPeerConnection.iceConnectionState returns a string which state of the ICE agent associated with the RTCPeerConnection: new, checking, connected, completed, failed, disconnected, and closed.

It describes the current state of the ICE agent and its connection to the ICE server; that is, the STUN or TURN server.

You can detect when this value has changed by watching for the iceconnectionstatechange event.

Syntax

 var state = RTCPeerConnection.iceConnectionState;

Value

The current state of the ICE agent and its connection. The value is one of the following strings:

new: The ICE agent is gathering addresses or is waiting to be given remote candidates through calls to RTCPeerConnection.addIceCandidate() (or both).
checking: The ICE agent has been given one or more remote candidates and is checking pairs of local and remote candidates against one another to try to find a compatible match, but has not yet found a pair which will allow the peer connection to be made. It is possible that gathering of candidates is also still underway.
connected: A usable pairing of local and remote candidates has been found for all components of the connection, and the connection has been established. It is possible that gathering is still underway, and it is also possible that the ICE agent is still checking candidates against one another looking for a better connection to use.
completed: The ICE agent has finished gathering candidates, has checked all pairs against one another, and has found a connection for all components.
failed: The ICE candidate has checked all candidates pairs against one another and has failed to find compatible matches for all components of the connection. It is, however, possible that the ICE agent did find compatible connections for some components.
disconnected: Checks to ensure that components are still connected failed for at least one component of the RTCPeerConnection. This is a less stringent test than failed and may trigger intermittently and resolve just as spontaneously on less reliable networks, or during temporary disconnections. When the problem resolves, the connection may return to the connected state.
closed: The ICE agent for this RTCPeerConnection has shut down and is no longer handling requests.

Example

var pc = new RTCPeerConnection();
var state = pc.iceConnectionState;

Specifications

Specification
WebRTC 1.0: Real-Time Communication Between Browsers (WebRTC 1.0) # dom-peerconnection-ice-connection-state

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`iceConnectionState`	26	15	52	No	15	11	≤37	26	Yes	14	11	1.5