AudioNode.numberOfOutputs

The numberOfOutputs property of the AudioNode interface returns the number of outputs coming out of the node. Destination nodes — like AudioDestinationNode — have a value of 0 for this attribute.

var numOutputs = audioNode.numberOfOutputs;

An integer ≥ 0.

const audioCtx = new AudioContext();

const oscillator = audioCtx.createOscillator();
const gainNode = audioCtx.createGain();

oscillator.connect(gainNode).connect(audioCtx.destination);

console.log(oscillator.numberOfOutputs); // 1
console.log(gainNode.numberOfOutputs); // 1
console.log(audioCtx.destination.numberOfOutputs); // 0

• Using the Web Audio API