Math.SQRT1_2

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The Math.SQRT1_2 static data property represents the square root of 1/2, which is approximately 0.707.

Try it

function getRoot1Over2() {
  return Math.SQRT1_2;
}

console.log(getRoot1Over2());
// Expected output: 0.7071067811865476

Value

\mathtt{Math.SQRT1_2} = \sqrt{\frac{1}{2}} \approx 0.707

Property attributes of `Math.SQRT1_2`
Writable	no
Enumerable	no
Configurable	no

Description

Math.SQRT1_2 is a constant and a more performant equivalent to Math.sqrt(0.5).

Because SQRT1_2 is a static property of Math, you always use it as Math.SQRT1_2, rather than as a property of a Math object you created (Math is not a constructor).

Examples

Using Math.SQRT1_2

The following function returns 1 over the square root of 2:

function getRoot1_2() {
  return Math.SQRT1_2;
}

getRoot1_2(); // 0.7071067811865476

Specifications

Specification
ECMAScript® 2026 Language Specification # sec-math.sqrt1_2