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

Syntax

dateObj.valueOf()

Return value

The number of milliseconds between 1 January 1970 00:00:00 UTC and the given date.

Description

The valueOf() method returns the primitive value of a Date object as a number data type, the number of milliseconds since midnight 01 January, 1970 UTC.

This method is functionally equivalent to the Date.prototype.getTime() method.

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

Examples

Using valueOf()

var x = new Date(56, 6, 17);
var myVar = x.valueOf();      // assigns -424713600000 to myVar

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

Document Tags and Contributors

 Contributors to this page: eduardoboucas, fscholz, Mingun, ethertank, Sheppy, evilpie, Ptak82, Maian, Dria
 Last updated by: eduardoboucas,