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SpeechSynthesisUtterance.onstart

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

The onstart property of the SpeechSynthesisUtterance interface represents an event handler that will run when the utterance has begun to be spoken (when the start event fires.)

This occurs when the SpeechSynthesis.speak() method is invoked.

Syntax

speechSynthesisUtteranceInstance.onstart = function() { ... };

Examples

var synth = window.speechSynthesis;

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

var voices = synth.getVoices();

  ...

inputForm.onsubmit = function(event) {
  event.preventDefault();

  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];
    }
  }

  synth.speak(utterThis);

  utterThis.onstart = function(event) {
    console.log('We have started uttering this speech: ' + event.utterance.text);
  }

  inputTxt.blur();
}

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
onstart
33
14
49
No
21
7
No
33
62
No
7
3.0

See also

© 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/SpeechSynthesisUtterance/onstart