files/en-us/web/api/speechsynthesisutterance/volume/index.md
{{APIRef("Web Speech API")}}
The volume property of the {{domxref("SpeechSynthesisUtterance")}} interface gets and sets the volume that the utterance will be spoken at.
If not set, the default value 1 will be used.
A float that represents the volume value, between 0 (lowest) and 1 (highest.)
If SSML is used, this value will be overridden by prosody tags in the markup.
const synth = window.speechSynthesis;
const inputForm = document.querySelector("form");
const inputTxt = document.querySelector("input");
const voiceSelect = document.querySelector("select");
const voices = synth.getVoices();
// …
inputForm.onsubmit = (event) => {
event.preventDefault();
const utterThis = new SpeechSynthesisUtterance(inputTxt.value);
const selectedOption =
voiceSelect.selectedOptions[0].getAttribute("data-name");
for (const voice of voices) {
if (voice.name === selectedOption) {
utterThis.voice = voice;
}
}
utterThis.volume = 0.5;
synth.speak(utterThis);
inputTxt.blur();
};
{{Specifications}}
{{Compat}}