MediaTrackConstraints: frameRate property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2017.

TheMediaTrackConstraints dictionary'sframeRate property is aConstrainDoubledescribing the requested or mandatory constraints placed upon the value of theframeRate constrainable property.

If needed, you can determine whether or not this constraint is supported by checkingthe value ofMediaTrackSupportedConstraints.frameRate as returned by acall toMediaDevices.getSupportedConstraints(). However, typically thisis unnecessary since browsers will ignore any constraints they're unfamiliar with.

Value

AConstrainDouble describing the acceptable or required value(s) for avideo track's frame rate, in frames per second.

If this value is a number, the user agent will attempt to obtain media whose frame rateis as close as possible to this number given the capabilities of the hardware and theother constraints specified. Otherwise, the value of thisConstrainDoublewill guide the user agent in its efforts to provide an exact match to the required framerate (ifexact is specified or bothmin andmaxare provided and have the same value) or to a best-possible value.