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

The RTCPeerConnection.onicecandidate property is an EventHandler which specifies a function to be called when the icecandidate event occurs on an RTCPeerConnection instance. This happens whenever the local ICE agent needs to deliver a message to the other peer through the signaling server. This lets the ICE agent perform negotiation with the remote peer without the browser itself needing to know any specifics about the technology being used for signaling; simply implement this method to use whatever messaging technology you choose to send the ICE candidate to the remote peer.


RTCPeerConnection.onicecandidate = eventHandler;


This should be set to a function which you provide that accepts as input an RTCPeerConnectionIceEvent object representing the icecandidate event. The function should deliver the ICE candidate, whose SDP can be found in the event's candidate property, to the remote peer through the signaling server.

If the event's candidate property is null, ICE gathering has finished.


The example below, which is based on the code from the article Signaling and video calling, sets up a handler for icecandidate events to send the candidates to the remote peer.

pc.onicecandidate = function(event) {
  if (event.candidate) {
    // Send the candidate to the remote peer
  } else {
    // All ICE candidates have been sent


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

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support561522 ?


37 — 43

FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support5656 Yes44


37 — 43


1. Promise based version.

See also

Document Tags and Contributors

Contributors to this page: fscholz, Sheppy, jpmedley, abbycar, nils, teoli, rmnguleria
Last updated by: fscholz,