Date.now

The Date.now() method returns the number of milliseconds elapsed since 1 January 1970 00:00:00 UTC.

Syntax

var timeInMs = Date.now();

Return value

A Number representing the milliseconds elapsed since the UNIX epoch.

Description

Because now() is a static method of Date, you always use it as Date.now().

Polyfill

This method was standardized in ECMA-262 5^th edition. Engines which have not been updated to support this method can work around the absence of this method using the following shim:

if (!Date.now) {
  Date.now = function now() {
    return new Date().getTime();
  };
}

Specifications

Specification	Status	Comment
ECMAScript 5.1 (ECMA-262) The definition of 'Date.now' in that specification.	Standard	Initial definition. Implemented in JavaScript 1.5.
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Date.now' in that specification.	Standard
ECMAScript 2017 Draft (ECMA-262) The definition of 'Date.now' in that specification.	Draft

Browser compatibility

See also

• Performance.now() — provides timestamps with sub-millisecond resolution for use in measuring web page performance
• console.time() / console.timeEnd()