JavaScript Math sign()

In this tutorial, you are going to learn about the JavaScript Math.sign() method with the help of examples.

The sign() method computes the sign of the specified number and returns 1 if the number is positive and -1 if it's negative.

Example

// sign() with a positive number
let value = Math.sign(126);
console.log(value); 

// Output:  1

sign() Syntax

The syntax of the Math.sign() method is:

Math.sign(number)

Here, sign() is a static method. Hence, we are accessing the method using the class name, Math.


sign() Parameter

The Math.sign() method takes a single parameter:

  • number - value whose sign is to be determined

sign() Return Value

The sign() method returns:

  • 1 if the argument is positive
  • -1 if the argument is negative
  • NaN (Not a Number) for a non-numeric argument

Example 1: JavaScript Math.sign()

// sign() with negative argument let value1 = Math.sign(-27);
console.log(value1);
// sign() with positive argument let value2 = Math.sign(16);
console.log(value2); // Output: // -1 // 1

Here, the Math.sign() returns

  • -1 - for the negative number -27
  • 1 - for the positive number 16

Example 2: Math.sign() with Non-Numeric Arguments

let string = "Harry";
// sign() with non-numeric argument let result = Math.sign(string);
console.log(result); // Output: NaN

In the above example, we have used the Math.sign() method with a string value "Harry". Hence, we get NaN as output.


Example 3: Math.sign() with Zero Values

// sign() with negative zero let value1 = Math.sign(-0);
console.log(value1); // Output: -0
// sign() with positive zero let value2 = Math.sign(0);
console.log(value2); // Output: 0

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