AudioNode.numberOfInputs

The numberOfInputs property of the AudioNode interface returns the number of inputs feeding the node. Source nodes are defined as nodes having a numberOfInputs property with a value of 0.

var numInputs = audioNode.numberOfInputs;

An integer ≥ 0.

const audioCtx = new AudioContext();

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

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

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

• Using the Web Audio API