Unary negation (-) - JavaScript 编辑

The unary negation operator (-) precedes its operand and negates it.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

Syntax

Operator: -x

Examples

Negating numbers

const x = 3;
const y = -x;

// y = -3
// x = 3

Negating non-numbers

The unary negation operator can convert a non-number into a number.

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

// y = -4

Specifications

Specification
ECMAScript (ECMA-262) The definition of 'Unary negation operator' in that specification.

Browser compatibility

BCD tables only load in the browser

See also

• Addition operator
• Subtraction operator
• Division operator
• Multiplication operator
• Remainder operator
• Exponentiation operator
• Increment operator
• Decrement operator
• Unary plus operator