The MediaTrackConstraints dictionary's sampleSize property is a ConstrainLong describing the requested or mandatory constraints placed upon the value of the sampleSize constrainable property.

If needed, you can determine whether or not this constraint is supported by checking the value of MediaTrackSupportedConstraints.sampleSize as returned by a call to MediaDevices.getSupportedConstraints(). However, typically this is unnecessary since browsers will simply ignore any constraints they're unfamiliar with.


var constraintsObject = { sampleSize: constraint };

constraintsObject.sampleSize = constraint;


If this value is a number, the user agent will attempt to obtain media whose sample size (in bits per linear sample) is as close as possible to this number given the capabilities of the hardware and the other constraints specified. Otherwise, the value of this ConstrainLong will guide the user agent in its efforts to provide an exact match to the required sample size (if exact is specified or both min and max are provided and have the same value) or to a best-possible value.

Since this property can only represent linear sample sizes, this constraint can only be met by devices that can produce audio with linear samples.


See "Example: Constraint exerciser" in Capabilities, constraints, and settings for an example.


Specification Status Comment
Media Capture and Streams
The definition of 'sampleSize' in that specification.
Editor's Draft Initial specification.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) No support No support (Yes) ?
Feature Android Android Webview Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support ? (Yes) No support No support ? ? (Yes)

See also

Document Tags and Contributors

 Contributors to this page: Sheppy
 Last updated by: Sheppy,