Math.sign()

The Math.sign() function returns either a positive or negative +/- 1, indicating the sign of a number passed into the argument. If the number passed into Math.sign() is 0, it will return a +/- 0. Note that if the number is positive, an explicit (+) will not be returned.

Syntax

Math.sign(x)

Parameters

x

A number. If this argument is not a number, it is implicitly converted to one.

Return value

A number representing the sign of the given argument:

  • If the argument is positive, returns 1.
  • If the argument is negative, returns -1.
  • If the argument is positive zero, returns 0.
  • If the argument is negative zero, returns -0.
  • Otherwise, NaN is returned.

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

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
sign
38
12
25
No
25
9
38
38
25
25
9
3.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/sign