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

The SpeechSynthesisUtterance interface of the Web Speech API represents a speech request. It contains the content the speech service should read and information about how to read it (e.g. language, pitch and volume.)


Returns a new SpeechSynthesisUtterance object instance.


SpeechSynthesisUtterance also inherits properties from its parent interface, EventTarget.

Gets and sets the language of the utterance.
Gets and sets the pitch at which the utterance will be spoken at.
Gets and sets the speed at which the utterance will be spoken at.
Gets and sets the text that will be synthesised when the utterance is spoken.
Gets and sets the voice that will be used to speak the utterance.
Gets and sets the volume that the utterance will be spoken at.

Event handlers

Fired when the spoken utterance reaches a word or sentence boundary.
Fired when the utterance has finished being spoken.
Fired when an error occurs that prevents the utterance from being succesfully spoken.
Fired when the spoken utterance reaches a named SSML "mark" tag.
Fired when the utterance is paused part way through.
Fired when a paused utterance is resumed.
Fired when the utterance has begun to be spoken.


In our basic Speech synthesiser demo, we first grab a reference to the SpeechSynthesis controller using window.speechSynthesis. After defining some necessary variables, we retrieve a list of the voices available using SpeechSynthesis.getVoices() and populate a select menu with them so the user can choose what voice they want.

Inside the inputForm.onsubmit handler, we stop the form submitting with preventDefault(),  use the constructor to create a new utterance instance containing the text from the text <input>, set the utterance's voice to the voice selected in the <select> element, and start the utterance speaking via the SpeechSynthesis.speak() method.

var synth = window.speechSynthesis;

var inputForm = document.querySelector('form');
var inputTxt = document.querySelector('input');
var voiceSelect = document.querySelector('select');

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);

inputForm.onsubmit = function(event) {

  var utterThis = new SpeechSynthesisUtterance(inputTxt.value);
  var selectedOption = voiceSelect.selectedOptions[0].getAttribute('data-name');
  for(i = 0; i < voices.length ; i++) {
    if(voices[i].name === selectedOption) {
      utterThis.voice = voices[i];


Specification Status Comment
Web Speech API
The definition of 'SpeechSynthesisUtterance' in that specification.

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 33 (Yes) 49 (49) No support (Yes) 7
Feature Android Chrome Edge Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) No support 2.0 No support No support 7.1

See also

Document Tags and Contributors

 Contributors to this page: MaulingMonkey, abbycar, chrisdavidmills
 Last updated by: MaulingMonkey,