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This API is available on Firefox OS for internal applications only.

The muted property of the Telephony interface indicates whether or not the microphone is muted for the purposes of telephony.


// Is the phone muted?
var muted = myTelephony.muted;

// Mutes the phone
myTelephony.muted = true;


 A Booleantrue indicates the microphone is muted; false indicates that it is not. You may read and write this value.


// Telephony object
var tel = navigator.mozTelephony;

// Receive a call
tel.onincoming = function (e) {
  var incomingCall =;

  // Answer the call

// Say we have a button that mutes/unmutes the phone
muteButton.onclick = function() {
  if(tel.muted) {
    tel.muted = false;
  } else {
    tel.muted = true;


Specification Status Comment
Web Telephony Draft Draft

Browser compatibility

For obvious reasons, support is primarily expected on mobile browsers.

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support No support No support No support No support No support
Feature Android Firefox Mobile (Gecko) Firefox OS (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support 12.0 (12.0) 1.0.1 No support No support No support

See also

Document Tags and Contributors

 Contributors to this page: chrisdavidmills, teoli, fscholz, jsx, kscarfone, Jeremie, Sheppy
 Last updated by: chrisdavidmills,