Web/API/Web Speech API

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

The Web Speech API enables you to incorporate voice data into web apps. The Web Speech API has two parts: SpeechSynthesis (Text-to-Speech), and SpeechRecognition (Asynchronous Speech Recognition.)

Web Speech Concepts and Usage

The Web Speech API makes web apps able to handle voice data. There are two components to this API:

• Speech recognition is accessed via the SpeechRecognition interface, which provides the ability to recognize voice context from an audio input (normally via the device's default speech recognition service) and respond appropriately. Generally you'll use the interface's constructor to create a new SpeechRecognition object, which has a number of event handlers available for detecting when speech is input through the device's microphone. The SpeechGrammar interface represents a container for a particular set of grammar that your app should recognise. Grammar is defined using JSpeech Grammar Format (JSGF.)
• Speech synthesis is accessed via the SpeechSynthesis interface, a text-to-speech component that allows programs to read out their text content (normally via the device's default speech synthesiser.) Different voice types are represented by SpeechSynthesisVoice objects, and different parts of text that you want to be spoken are represented by SpeechSynthesisUtterance objects. You can get these spoken by passing them to the SpeechSynthesis.speak() method.

For more details on using these features, see Using the Web Speech API.

Web Speech API Interfaces

Speech recognition

SpeechRecognition

The controller interface for the recognition service; this also handles the SpeechRecognitionEvent sent from the recognition service.

SpeechRecognitionAlternative

Represents a single word that has been recognised by the speech recognition service.

SpeechRecognitionError

Represents error messages from the recognition service.

SpeechRecognitionEvent

The event object for the result and nomatch events, and contains all the data associated with an interim or final speech recognition result.

SpeechGrammar

The words or patterns of words that we want the recognition service to recognize.

SpeechGrammarList

Represents a list of SpeechGrammar objects.

SpeechRecognitionResult

Represents a single recognition match, which may contain multiple SpeechRecognitionAlternative objects.

SpeechRecognitionResultList

Represents a list of SpeechRecognitionResult objects, or a single one if results are being captured in continuous mode.

Speech synthesis

SpeechSynthesis

The controller interface for the speech service; this can be used to retrieve information about the synthesis voices available on the device, start and pause speech, and other commands besides.

SpeechSynthesisErrorEvent

Contains information about any errors that occur while processing SpeechSynthesisUtterance objects in the speech service.

SpeechSynthesisEvent

Contains information about the current state of SpeechSynthesisUtterance objects that have been processed in the speech service.

SpeechSynthesisUtterance

Represents a speech request. It contains the content the speech service should read and information about how to read it (e.g. language, pitch and volume.)

SpeechSynthesisVoice

Represents a voice that the system supports. Every SpeechSynthesisVoice has its own relative speech service including information about language, name and URI.

Window.speechSynthesis

Specced out as part of a [NoInterfaceObject] interface called SpeechSynthesisGetter, and Implemented by the Window object, the speechSynthesis property provides access to the SpeechSynthesis controller, and therefore the entry point to speech synthesis functionality.

Examples

The Web Speech API repo on GitHub contains demos to illustrate speech recognition and synthesis.

Specifications

Specification	Status	Comment
Web Speech API	Draft	Initial definition

Browser compatibility

SpeechRecognition

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
SpeechRecognition Experimental'	Chrome Full support 33 Prefixed' Notes' Full support 33 Prefixed' Notes' Prefixed' Implemented with the vendor prefix: webkit Notes' You'll need to serve your code through a web server for recognition to work.	Edge Full support ≤79 Prefixed' Notes' Full support ≤79 Prefixed' Notes' Prefixed' Implemented with the vendor prefix: webkit Notes' You'll need to serve your code through a web server for recognition to work.	Firefox No support No	IE No support No	Opera No support No	Safari No support No	WebView Android Full support 4.4.3 Prefixed' Notes' Full support 4.4.3 Prefixed' Notes' Prefixed' Implemented with the vendor prefix: webkit Notes' You'll need to serve your code through a web server for recognition to work.	Chrome Android Full support 33 Prefixed' Notes' Full support 33 Prefixed' Notes' Prefixed' Implemented with the vendor prefix: webkit Notes' You'll need to serve your code through a web server for recognition to work.	Firefox Android No support No	Opera Android No support No	Safari iOS No support No	Samsung Internet Android Full support 2.0 Prefixed' Notes' Full support 2.0 Prefixed' Notes' Prefixed' Implemented with the vendor prefix: webkit Notes' You'll need to serve your code through a web server for recognition to work.

Legend

Full support  

Full support

No support  

No support

Experimental. Expect behavior to change in the future.'

Experimental. Expect behavior to change in the future.

See implementation notes.'

See implementation notes.

Requires a vendor prefix or different name for use.'

Requires a vendor prefix or different name for use.

SpeechSynthesis

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
SpeechSynthesis Experimental'	Chrome Full support 33	Edge Full support ≤18	Firefox Full support 49	IE No support No	Opera Full support 21	Safari Full support 7	WebView Android Full support 4.4.3	Chrome Android Full support 33	Firefox Android Full support 62 Full support 62 No support 61 — 62 Disabled' Disabled' From version 61 until version 62 (exclusive): this feature is behind the media.webspeech.synth.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.	Opera Android No support No	Safari iOS Full support 7	Samsung Internet Android Full support 3.0

Legend

Full support  

Full support

No support  

No support

Experimental. Expect behavior to change in the future.'

Experimental. Expect behavior to change in the future.

User must explicitly enable this feature.'

User must explicitly enable this feature.

See also

• Using the Web Speech API
• SitePoint article
• HTML5Rocks article
• Demo [aurelio.audero.it]

Web Speech API by Mozilla Contributors is licensed under CC-BY-SA 2.5.