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The Math.LOG2E property represents the base 2 logarithm of e, approximately 1.442:

Math.LOG2E=log2(e)1.442\mathtt{\mi{Math.LOG2E}} = \log_2(e) \approx 1.442

Property attributes of Math.LOG2E
Writable no
Enumerable no
Configurable no

Description

Because LOG2E is a static property of Math, you always use it as Math.LOG2E, rather than as a property of a Math object you created (Math is not a constructor).

Examples

Using Math.LOG2E

The following function returns the base 2 logarithm of e:

function getLog2e() {
  return Math.LOG2E;
}

getLog2e(); // 1.4426950408889634

Specifications

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.LOG2E' in that specification.
Standard  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Math.LOG2E' in that specification.
Standard  
ECMAScript 2017 Draft (ECMA-262)
The definition of 'Math.LOG2E' in that specification.
Draft  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

See also

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