ThegetTime() method ofDate instances returns the number of milliseconds for this date since theepoch, which is defined as the midnight at the beginning of January 1, 1970, UTC.

Try it

const moonLanding = new Date("July 20, 69 20:17:40 GMT+00:00");// Milliseconds since Jan 1, 1970, 00:00:00.000 GMTconsole.log(moonLanding.getTime());// Expected output: -14182940000

Syntax

getTime()

Parameters

None.

Return value

A number representing thetimestamp, in milliseconds, of this date. ReturnsNaN if the date isinvalid.

Description

Date objects are fundamentally represented by atimestamp, and this method allows you to retrieve the timestamp. You can use this method to help assign a date and time to anotherDate object. This method is functionally equivalent to thevalueOf() method.

Examples

Using getTime() for copying dates

Constructing a date object with the identical time value.

// Since month is zero based, birthday will be January 10, 1995const birthday = new Date(1994, 12, 10);const copy = new Date();copy.setTime(birthday.getTime());

Measuring execution time

Subtracting two subsequentgetTime() calls on newly generatedDate objects, give the time span between these two calls. This can be used to calculate the executing time of some operations. See alsoDate.now() to prevent instantiating unnecessaryDate objects.

let end, start;start = new Date();for (let i = 0; i < 1000; i++) {  Math.sqrt(i);}end = new Date();console.log(`Operation took ${end.getTime() - start.getTime()} msec`);

Specifications

Browser compatibility

See also

• Date.prototype.setTime()
• Date.prototype.valueOf()
• Date.now()