Math

`Math.sqrt`

Returns the square root of a number

Syntax

JavaScript

Math.sqrt(x)

Parameters

Parameter	Type	Description
x	number	A non-negative number

Return Value

The square root of x, or NaN if x is negative

Examples

Basic Usage

console.log(Math.sqrt(9)); // 3
console.log(Math.sqrt(2)); // 1.4142135623730951

Practical Example

function distance(x1: number, y1: number, x2: number, y2: number) {
  return Math.sqrt((x2 - x1) ** 2 + (y2 - y1) ** 2);
}
console.log(distance(0, 0, 3, 4)); // 5

Advanced Usage

console.log(Math.sqrt(-1)); // NaN
console.log(Math.sqrt(0)); // 0

Understanding Math.sqrt

The Math.sqrt method in JavaScript returns the square root of a number. It belongs to the Math object and is one of the most widely used methods for working with math values in modern JavaScript and TypeScript applications.

The method signature is Math.sqrt(x). It accepts 1 parameter: x. When called, it returns the square root of x, or nan if x is negative. Understanding when and how to use sqrt() helps you write more expressive, readable code.

Common use cases for Math.sqrt include data transformation, input validation, API response processing, and building reusable utility functions. It works well alongside related methods like math-cbrt, math-pow, math-hypot, enabling you to chain operations together for complex data manipulation pipelines.

Browser support for Math.sqrt is excellent across all modern browsers including Chrome, Firefox, Safari, and Edge. It is also fully supported in Node.js and Deno. For older environments, transpilation with Babel or a polyfill may be needed.