乗算 (*)
BaselineWidely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
乗算演算子 (*) はオペランドの積を生成します。
試してみましょう
console.log(3 * 4);// Expected output: 12console.log(-3 * 4);// Expected output: -12console.log("3" * 2);// Expected output: 6console.log("foo" * 2);// Expected output: NaN構文
js
x * y;例
数値を用いた乗算
js
2 * 2; // 4-2 * 2; // -4無限大との乗算
js
Infinity * 0; // NaNInfinity * Infinity; // Infinity非数との乗算
js
"foo" * 2; // NaN仕様書
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-multiplicative-operators |