SpeechSynthesisUtterance.pitch

The pitch property of the SpeechSynthesisUtterance interface gets and sets the pitch at which the utterance will be spoken at.

If unset, a default value of 1 will be used.

Syntax

var myPitch = speechSynthesisUtteranceInstance.pitch;
speechSynthesisUtteranceInstance.pitch = 1.5;

Value

A float representing the pitch value. It can range between 0 (lowest) and 2 (highest), with 1 being the default pitch for the current platform or voice. Some speech synthesis engines or voices may constrain the minimum and maximum rates further. If SSML is used, this value will be overridden by prosody tags in the markup.

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];
    }
  }
  utterThis.pitch = 1.5;
  synth.speak(utterThis);
  inputTxt.blur();
}

Specifications

Browser compatibility

• [1] Can be enabled via the media.webspeech.synth.enabled flag in about:config.

See also

• Web Speech API