This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

The emma read-only property of the SpeechRecognitionEvent interface returns an Extensible MultiModal Annotation markup language (EMMA) — XML — representation of the result.

Note: EMMA is defined in the specification EMMA: Extensible MultiModal Annotation markup language. You can see muliple EMMA examples in the spec.


var myEmma = event.emma;


A valid XML document. The exact contents can vary across user agents and recognition engines, but all supporting implementations will expose a valid XML document complete with an EMMA namespace. If the speech recognition system does not supply EMMA data then the user agent will return null.


recognition.onresult = function(event) {
  var color = event.results[0][0].transcript;
  diagnostic.textContent = 'Result received: ' + color + '.';
  bg.style.backgroundColor = color;

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