SpeechRecognition: nomatch event

The nomatch event of the Web Speech API is fired when the speech recognition service returns a final result with no significant recognition.

This may involve some degree of recognition, which doesn't meet or exceed the confidence threshold.

You can use the nomatch event in an addEventListener method:

var recognition = new webkitSpeechRecognition() || new SpeechRecognition();

recognition.addEventListener('nomatch', function() {
  console.log('Speech not recognized');
});

Or use the onnomatch event handler property:

recognition.onnomatch = function() {
  console.log('Speech not recognized');
}

• Web Speech API