files/en-us/web/javascript/reference/global_objects/math/sign/index.md

metadata

title: Math.sign()
short-title: sign()
slug: Web/JavaScript/Reference/Global_Objects/Math/sign
page-type: javascript-static-method
browser-compat: javascript.builtins.Math.sign
sidebar: jsref

The Math.sign() static method returns 1 or -1, indicating the sign of the number passed as argument. If the input is 0 or -0, it will be returned as-is.

{{InteractiveExample("JavaScript Demo: Math.sign()")}}

console.log(Math.sign(3));
// Expected output: 1

console.log(Math.sign(-3));
// Expected output: -1

console.log(Math.sign(0));
// Expected output: 0

console.log(Math.sign("-3"));
// Expected output: -1

Syntax

Math.sign(x)

Parameters

• x
  • : A number.

Return value

A number representing the sign of x:

• If x is positive, returns 1.
• If x is negative, returns -1.
• If x is positive zero, returns 0.
• If x is negative zero, returns -0.
• Otherwise, returns {{jsxref("NaN")}}.

Description

Because sign() is a static method of Math, you always use it as Math.sign(), rather than as a method of a Math object you created (Math is not a constructor).

Examples

Using Math.sign()

Math.sign(3); // 1
Math.sign(-3); // -1
Math.sign("-3"); // -1
Math.sign(0); // 0
Math.sign(-0); // -0
Math.sign(NaN); // NaN
Math.sign("foo"); // NaN
Math.sign(); // NaN

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• Polyfill of Math.sign in core-js
• es-shims polyfill of Math.sign
• {{jsxref("Math.abs()")}}
• {{jsxref("Math.ceil()")}}
• {{jsxref("Math.floor()")}}
• {{jsxref("Math.round()")}}
• {{jsxref("Math.trunc()")}}