This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The read-only property RTCPeerConnection.iceGatheringState returns an enum of type RTCIceGatheringState that describes connection's ICE gathering state. This lets you detect, for example, when collection of ICE candidates has finished.

You can detect when the value of this property changes by watching for an event of type icegatheringstatechange.


 var state = RTCPeerConnection.iceGatheringState;


The possible values are those of an enum of type RTCIceGatheringState.

RTCIceGatheringState enum

The RTCIceGatheringState enum defines string constants which reflect the current status of ICE gathering, as returned using the RTCPeerConnection.iceGatheringState property. You can detect when this value changes by watching for an event of type icegatheringstatechange.

Constant Description
"new" The peer connection was just created and hasn't done any networking yet.
"gathering" The ICE agent is in the process of gathering candidates for the connection.
"complete" The ICE agent has finished gathering candidates. If something happens that requires collecting new candidates, such as a new interface being added or the addition of a new ICE server, the state will revert to "gathering" to gather those candidates.


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


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

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes)[1] (Yes) 22 (22) [1] No support (Yes) ?
Feature Android Webview Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes)[1] (Yes)[1] (Yes) 22.0 (22) [1] No support ? ?

[1] Though this property is not prefixed, the interface it belongs to was until Chrome 56.

[2] Though this property is not prefixed, the interface it belongs to is, until Firefox 44.

See also

Document Tags and Contributors

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