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

The SpeechRecognitionResult interface of the Web Speech API represents a single recognition match, which may contain multiple SpeechRecognitionAlternative objects.


SpeechRecognitionResult.isFinal Read only
A Boolean that states whether this result is final (true) or not (false) — if so, then this is the final time this result will be returned; if not, then this result is an interim result, and may be updated later on.
SpeechRecognitionResult.length Read only
Returns the length of the "array" — the number of SpeechRecognitionAlternative objects contained in the result (also referred to as "n-best alternatives".)


A standard getter that allows SpeechRecognitionAlternative objects within the result to be accessed via array syntax.


This code is excerpted from our Speech color changer example.

recognition.onresult = function(event) {
  // The SpeechRecognitionEvent results property returns a SpeechRecognitionResultList object
  // The SpeechRecognitionResultList object contains SpeechRecognitionResult objects.
  // It has a getter so it can be accessed like an array
  // The first [0] returns the SpeechRecognitionResult at position 0.
  // Each SpeechRecognitionResult object contains SpeechRecognitionAlternative objects that contain individual results.
  // These also have getters so they can be accessed like arrays.
  // The second [0] returns the SpeechRecognitionAlternative at position 0.
  // We then return the transcript property of the SpeechRecognitionAlternative object
  var color = event.results[0][0].transcript;
  diagnostic.textContent = 'Result received: ' + color + '.';
  bg.style.backgroundColor = color;


Specification Status Comment
Web Speech API
The definition of 'SpeechRecognitionResult' in that specification.

Browser compatibility

BCD tables only load in the browser

Firefox OS permissions

To use speech recognition in an app, you need to specify the following permissions in your manifest:

"permissions": {
  "audio-capture" : {
    "description" : "Audio capture"
  "speech-recognition" : {
    "description" : "Speech recognition"

You also need a privileged app, so you need to include this as well:

  "type": "privileged"

See also