Web/API/AudioBuffer/duration

From Get docs

The duration property of the AudioBuffer interface returns a double representing the duration, in seconds, of the PCM data stored in the buffer.


Syntax

var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate);
myArrayBuffer.duration;

Value

A double.

Example

// Stereo
var channels = 2;

// Create an empty two second stereo buffer at the
// sample rate of the AudioContext
var frameCount = audioCtx.sampleRate * 2.0;
var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate);

button.onclick = function() {
  // Fill the buffer with white noise;
  // just random values between -1.0 and 1.0
  for (var channel = 0; channel < channels; channel++) {
    // This gives us the actual ArrayBuffer that contains the data
    var nowBuffering = myArrayBuffer.getChannelData(channel);
    for (var i = 0; i < frameCount; i++) {
      // Math.random() is in [0; 1.0]
      // audio needs to be in [-1.0; 1.0]
      nowBuffering[i] = Math.random() * 2 - 1;
    }
  }

  console.log(myArrayBuffer.duration);
}

Specification

Specification Status Comment
Web Audio APIThe definition of 'duration' in that specification. Working Draft  

Browser compatibility

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
duration Chrome

Full support 14

Edge

Full support 12

Firefox

Full support 25

IE

No support No

Opera

Full support 15

Safari

Full support 6

WebView Android

Full support Yes

Chrome Android

Full support 18

Firefox Android

Full support 26

Opera Android

Full support 14

Safari iOS

Full support 6

Samsung Internet Android

Full support 1.0

Legend

Full support  
Full support
No support  
No support


See also