SpeechSynthesisVoice.localService

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

The localService read-only property of the SpeechSynthesisVoice interface returns a Boolean indicating whether the voice is supplied by a local speech synthesizer service (true), or a remote speech synthesizer service (false.)

This property is provided to allow differentiation in the case that some voice options are provided by a remote service; it is possible that remote voices might have extra latency, bandwidth or cost associated with them, so such distinction may be useful.

Syntax

var amILocal = speechSynthesisVoiceInstance.localService;

Value

A Boolean.

Examples

for(i = 0; i < voices.length ; i++) {
  var option = document.createElement('option');
  option.textContent = voices[i].name + ' (' + voices[i].lang + ')';

  if(voices[i].default) {
    option.textContent += ' -- DEFAULT';
  }

  console.log(voices[i].localService);

  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 'localService' in that specification.
Draft

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
localService
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