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.

Supported in Firefox OS 1.0.1.

See also

Document Tags and Contributors

Last updated by: mdnwebdocs-bot,