The pan property of the StereoPannerNode interface is an a-rate AudioParam representing the amount of panning to apply. The value can range between -1 (full left pan) and 1 (full right pan).


var audioCtx = new AudioContext();
var panNode = audioCtx.createStereoPanner();
panNode.pan.value = -0.5;

Returned value

An a-rate AudioParam containing the panning to apply.

Note: Though the AudioParam returned is read-only, the value it represents is not.


In our StereoPannerNode example (see source code) HTML we have a simple <audio> element along with a slider <input> to increase and decrease pan value. In the JavaScript we create a MediaElementAudioSourceNode and a StereoPannerNode, and connect the two together using the connect() method. We then use an oninput event handler to change the value of the StereoPannerNode.pan parameter and update the pan value display when the slider is moved.

Moving the slider left and right while the music is playing pans the music across to the left and right speakers of the output, respectively.

var audioCtx = new (window.AudioContext || window.webkitAudioContext)();
var myAudio = document.querySelector('audio');

var panControl = document.querySelector('.panning-control');
var panValue = document.querySelector('.panning-value');

pre.innerHTML = myScript.innerHTML;

// Create a MediaElementAudioSourceNode
// Feed the HTMLMediaElement into it
var source = audioCtx.createMediaElementSource(myAudio);

// Create a stereo panner
var panNode = audioCtx.createStereoPanner();

// Event handler function to increase panning to the right and left
// when the slider is moved

panControl.oninput = function() {
  panNode.pan.setValueAtTime(panControl.value, audioCtx.currentTime);
  panValue.innerHTML = panControl.value;

// connect the MediaElementAudioSourceNode to the panNode
// and the panNode to the destination, so we can play the
// music and adjust the panning using the controls


Specification Status Comment
Web Audio API
The definition of 'pan' in that specification.
Working Draft

Browser compatibility

ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
panChrome Full support 41Edge Full support 12Firefox Full support 37IE No support NoOpera Full support 28Safari No support NoWebView Android Full support 41Chrome Android Full support 41Firefox Android Full support 37Opera Android Full support 28Safari iOS No support NoSamsung Internet Android Full support 4.0


Full support
Full support
No support
No support

See also