SpeechSynthesis: voiceschanged event

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

The voiceschanged event of the Web Speech API is fired when the list of SpeechSynthesisVoice objects that would be returned by the SpeechSynthesis.getVoices() method has changed (when the voiceschanged event fires.)

Bubbles No
Cancelable No
Interface Event
Event handler property onvoiceschanged

Examples

This could be used to repopulate a list of voices that the user can choose between when the event fires. You can use the voiceschanged event in an addEventListener method:

var synth = window.speechSynthesis;

synth.addEventListener('voiceschanged', function() {
  var voices = synth.getVoices();
  for(i = 0; i < voices.length ; i++) {
    var option = document.createElement('option');
    option.textContent = voices[i].name + ' (' + voices[i].lang + ')';
    option.setAttribute('data-lang', voices[i].lang);
    option.setAttribute('data-name', voices[i].name);
    voiceSelect.appendChild(option);
  }
});

Or use the onvoiceschanged event handler property:

synth.onvoiceschanged = function() {
  var voices = synth.getVoices();
  for(i = 0; i < voices.length ; i++) {
    var option = document.createElement('option');
    option.textContent = voices[i].name + ' (' + voices[i].lang + ')';
    option.setAttribute('data-lang', voices[i].lang);
    option.setAttribute('data-name', voices[i].name);
    voiceSelect.appendChild(option);
  }
}

Specifications

Specification Status Comment
Web Speech API
The definition of 'speech synthesis events' in that specification.
Draft

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
voiceschanged event
Experimental
Chrome Full support 33Edge Full support 14Firefox Full support 49IE No support NoOpera Full support 21Safari Full support 7WebView Android Full support 4.4.3Chrome Android Full support 33Firefox Android Full support 62
Full support 62
No support 61 — 62
Disabled
Disabled From version 61 until version 62 (exclusive): this feature is behind the media.webspeech.synth.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.
Opera Android No support NoSafari iOS Full support 7Samsung Internet Android Full support 3.0

Legend

Full support
Full support
No support
No support
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
User must explicitly enable this feature.
User must explicitly enable this feature.

See also