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

Math.SQRT1_2=12=120.707\mathtt{\mi{Math.SQRT1_2}} = \sqrt{\frac{1}{2}} = \frac{1}{\sqrt{2}} \approx 0.707

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


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).


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


Specification Status Comment
ECMAScript 1st Edition (ECMA-262) Standard Initial definition. Implemented in JavaScript 1.0.
ECMAScript 5.1 (ECMA-262)
The definition of 'Math.SQRT1_2' in that specification.
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Math.SQRT1_2' in that specification.
ECMAScript Latest Draft (ECMA-262)
The definition of 'Math.SQRT1_2' in that specification.

Browser compatibility

FeatureChromeFirefoxEdgeInternet ExplorerOperaSafari
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)
FeatureAndroidChrome for AndroidEdge mobileFirefox for AndroidIE mobileOpera AndroidiOS Safari
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)

See also

Document Tags and Contributors

 Last updated by: fscholz,