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 |
| Target objects | SpeechSynthesisUtterance |
| 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.');
}
Inheritance
The boundary event implements the SpeechSynthesisEvent interface, which inherits from Event. It therefore has available the properties and methods defined on both these interfaces.
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a:hover text { fill: #0095DD; pointer-events: all;}
Specifications
| Specification | Status | Comment |
|---|---|---|
| Web Speech API The definition of 'speech synthesis utterance events' in that specification. |
Draft |
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) | 44 (44) [1] | No support | No support | No support |
| Feature | Android | Chrome | Edge | Firefox Mobile (Gecko) | Firefox OS | IE Phone | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|---|---|
| Basic support | ? | (Yes) | (Yes) | ? | 2.5 | No support | No support | No support |
- [1] Can be enabled via the
media.webspeech.synth.enabledflag in about:config.