SpeechSynthesisUtterance: boundary event

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

The boundary event of the Web Speech API is fired when the spoken utterance reaches a word or sentence boundary.

Bubbles No
Cancelable No
Interface SpeechSynthesisEvent
Event handler onboundary

Examples

You can use the boundary event in an addEventListener method:

utterThis.addEventListener('boundary', function(event) { 
  console.log(event.name + ' boundary reached after ' + event.elapsedTime + ' milliseconds.');
});

Or use the onboundary event handler property:

utterThis.onboundary = function(event) {
  console.log(event.name + ' boundary reached after ' + event.elapsedTime + ' milliseconds.');
}

Specifications

Specification Status Comment
Web Speech API
The definition of 'speech synthesis utterance events' in that specification.		 Draft  

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
boundary event
Experimental
Chrome Full support 33Edge Full support 14Firefox Full support 49IE No support NoOpera Full support 21Safari Full support 7WebView Android No support NoChrome 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