Number.prototype.valueOf()

The valueOf() method returns the wrapped primitive value of a Number object.

Syntax

numObj.valueOf()

Return value

A number representing the primitive value of the specified Number object.

Description

This method is usually called internally by JavaScript and not explicitly in web code.

Examples

Using valueOf

var numObj = new Number(10);
console.log(typeof numObj); // object

var num = numObj.valueOf();
console.log(num);           // 10
console.log(typeof num);    // number

Specifications

Specification Status Comment
ECMAScript 1st Edition (ECMA-262) Standard Initial definition. Implemented in JavaScript 1.1.
ECMAScript 5.1 (ECMA-262)
The definition of 'Number.prototype.valueOf' in that specification.		 Standard  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Number.prototype.valueOf' in that specification.		 Standard  
ECMAScript Latest Draft (ECMA-262)
The definition of 'Number.prototype.valueOf' in that specification.		 Draft  

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
valueOfChrome Full support YesEdge Full support YesFirefox Full support 1IE Full support YesOpera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesFirefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes

Legend

Full support  
Full support

See also

Related Topics
  1. Standard built-in objects
  2. Number
  3. Properties
    1. Number.EPSILON
    2. Number.MAX_SAFE_INTEGER
    3. Number.MAX_VALUE
    4. Number.MIN_SAFE_INTEGER
    5. Number.MIN_VALUE
    6. Number.NEGATIVE_INFINITY
    7. Number.NaN
    8. Number.POSITIVE_INFINITY
    9. Number.prototype
  4. Methods
    1. Number.isFinite()
    2. Number.isInteger()
    3. Number.isNaN()
    4. Number.isSafeInteger()
    5. Number.parseFloat()
    6. Number.parseInt()
    7. Number.prototype.toExponential()
    8. Number.prototype.toFixed()
    9. Number.prototype.toLocaleString()
    10. Number.prototype.toPrecision()
    11. Number.prototype.toSource()
    12. Number.prototype.toString()
    13. Number.prototype.valueOf()
    14. Number.toInteger()
  5. Inheritance:
  6. Function
  7. Properties
    1. Function.arguments
    2. Function.arity
    3. Function.caller
    4. Function.displayName
    5. Function.length
    6. Function.name
    7. Function.prototype
  8. Methods
    1. Function.prototype.apply()
    2. Function.prototype.bind()
    3. Function.prototype.call()
    4. Function.prototype.isGenerator()
    5. Function.prototype.toSource()
    6. Function.prototype.toString()
  9. Object
  10. Properties
    1. Object.prototype.__count__
    2. Object.prototype.__noSuchMethod__
    3. Object.prototype.__parent__
    4. Object.prototype.__proto__
    5. Object.prototype.constructor
  11. Methods
    1. Object.prototype.__defineGetter__()
    2. Object.prototype.__defineSetter__()
    3. Object.prototype.__lookupGetter__()
    4. Object.prototype.__lookupSetter__()
    5. Object.prototype.hasOwnProperty()
    6. Object.prototype.isPrototypeOf()
    7. Object.prototype.propertyIsEnumerable()
    8. Object.prototype.toLocaleString()
    9. Object.prototype.toSource()
    10. Object.prototype.toString()
    11. Object.prototype.unwatch()
    12. Object.prototype.valueOf()
    13. Object.prototype.watch()
    14. Object.setPrototypeOf()