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

The addModule() method of the Worklet interface loads the module in the given JavaScript file and adds it to the current Worklet.


addPromise = worklet.addModule(moduleURL);
addPromise = worklet.addModule(moduleURL, options);


A String containing the URL of a JavaScript file with the module to add.
options Optional
An object with any of the following options:
  • credentials: A RequestCredentials value that indicates whether to send credentials (e.g. cookies and HTTP authentification) when loading the module. Can be one of "omit", "same-origin", or "include". Defaults to "same-origin". See also Request.credentials.

Return value

A Promise that resolves once the module from the given URL has been added. The promise doesn't return any value.


If addModule() fails, it rejects the promise, delivering one of the following errors to the rejection handler.

The specified script is invalid or could not be loaded.
The specified moduleURL is invalid.


AudioWorklet example

const audioCtx = new AudioContext();
const audioWorklet = audioCtx.audioWorklet;
await audioWorklet.addModule('modules/bypassFilter.js', {
  credentials: 'omit',

PaintWorklet example


Once a paintWorklet is included, the CSS paint() function can be used to include the image created by the worklet:

@supports (background-image: paint(id)) {
  h1 {
      background-image: paint(hollowHighlights, filled, 3px);


Specification Status Comment
Worklets Level 1
The definition of 'addModule()' in that specification.
Working Draft

Browser compatibility

Update compatibility data on GitHub
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
addModuleChrome Full support 65Edge Full support 79Firefox Full support 76IE No support NoOpera Full support 52Safari No support NoWebView Android Full support 65Chrome Android Full support 65Firefox Android Full support 79Opera Android Full support 47Safari iOS No support NoSamsung Internet Android Full support 9.0


Full support  
Full support
No support  
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