SpeechSynthesisEvent: SpeechSynthesisEvent() constructor

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨September 2022⁩.

TheSpeechSynthesisEvent() constructor creates a newSpeechSynthesisEvent object.

Note:A web developer doesn't typically need to call this constructor, as the browser creates these objects itself when firing events.

Syntax

new SpeechSynthesisEvent(type, options)

A string with the name of the event.It is case-sensitive and browsers set it tostart,end,error,pause,resume,mark, orboundary.

An object that,in addition to the properties defined inEvent(), has the following properties:

utterance: ASpeechSynthesisUtterance object, which is the speech request the event was triggered on.
charIndexOptional: The index position of the character inSpeechSynthesisUtterance.text that was being spoken when the event was triggered. Its default value is0.
charLengthOptional: The number of characters left to be spoken after the character at thecharIndex position. Its default value is0.
elapsedTimeOptional: The elapsed time in seconds, after theSpeechSynthesisUtterance.text started being spoken, at which the event was triggered. Its default value is0.
nameOptional: The name associated with certain types of events: the name of theSSML marker reached in the case of amark event, or the type of boundary reached in the case of aboundary event. It defaults to the empty string ("").