一元减(-)

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

一元减-)运算符在其操作数之前,并对其取反。

尝试一下

const x = 4;
const y = -x;

console.log(y);
// Expected output: -4

const a = "4";
const b = -a;

console.log(b);
// Expected output: -4

语法

js
-x

示例

数字取反

js
const x = 3;
const y = -x;

// y = -3
// x = 3

非数字取反

一元减运算符可以将非数字转换为数字

js
const x = "4";
const y = -x;

// y = -4

规范

Specification
ECMAScript® 2025 Language Specification
# sec-unary-minus-operator

浏览器兼容性

Report problems with this compatibility data on GitHub
desktopmobileserver
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Deno
Node.js
Unary negation (-)

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support

参见