JavaScript Square Root operation

Finding Square Root number in JavaScript

Posted on January 02, 2021


To find the Square Root value of a certain number, you can use the JavaScript Math.sqrt() method. You need to pass the number into the method as follows:

Math.sqrt(9);
// returns 3

If you pass a negative number to the method, it will return NaN instead of a number:

Math.sqrt(-9);
// returns NaN

The method only accepts one parameter. When you pass more than one parameter, the rest is ignored:

Math.sqrt(9, 18, 27);
// returns 3

Square Root constants in JavaScript

The Math object also has two static square root properties that you can use in your code immediately. They are:

  • Math.SQRT1_2 which returns the Square Root value of 1/2
  • Math.SQRT2 which returns the Square Root value of 2

Since both are static properties, you can use them just like a normal variable:

console.log(`The Square Root of 1/2 is ${Math.SQRT1_2}`);
console.log(`The Square Root of 2 is ${Math.SQRT2}`);

Related articles:

Grab the free JavaScript book today 👍

Learn the building blocks of JavaScript programming language like data types, functions, objects, arrays and classes.

Use the knowledge from the book to build a small but solid program.

Learn more