SpeechSynthesisVoice

The default read-only property of the indicating whether the voice is the default voice for the current app (true), or not (false.) A boolean value.

The lang read-only property of the SpeechSynthesisVoice interface returns a BCP 47 language tag indicating the language of the voice.

The localService read-only property of the indicating whether the voice is supplied by a local speech synthesizer service (true), or a remote speech synthesizer service (false.) This property is provided to allow differentiation in the case that some voice options are provided by a remote service; it is possible that remote voices might have extra latency, bandwidth or cost associated with them, so such distinction may be useful.

The name read-only property of the represents the voice.

The voiceURI read-only property of the the speech synthesis service for this voice.