How to get time in milliseconds since the unix epoch in Javascript?

Question

Possible Duplicate:
How do you get a timestamp in JavaScript?
Calculating milliseconds from epoch

How can I get the current epoch time in Javascript? Basically the number of milliseconds since midnight, 1970-01-01.

Note that this question (and some duplicates) ask for milliseconds since epoch. While JavaScript gives you this, note that standard Unix epoch is usually expression in seconds (1/1000 the value you get from JS). — Phrogz, Mar 05 '12 at 23:48
`new Date/1E3|0` - instantiate `Date`, coerce to number, divide by 1000 and floor. — Camilo Martin, Dec 15 '12 at 04:13
@CamiloMartin You should write this an an answer. It's the best. — Justin Noel, Nov 25 '14 at 14:26
@Justin Thanks! But note that, since I wrote that, IE8 has become the kind of browser that you may be ready to say "no" to. If you're ready to discard IE8 support, use this: `Date.now()` (easily shimmable otherwise). — Camilo Martin, Nov 25 '14 at 23:51

Paul · Accepted Answer · 2019-09-19T18:20:28.897

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Date.now() returns a unix timestamp in milliseconds.

const now = Date.now(); // Unix timestamp in milliseconds
console.log( now );

Prior to ECMAScript5 (I.E. Internet Explorer 8 and older) you needed to construct a Date object, from which there are several ways to get a unix timestamp in milliseconds:

console.log( +new Date );
console.log( (new Date).getTime() );
console.log( (new Date).valueOf() );

edited Sep 19 '19 at 18:20

answered Mar 05 '12 at 23:46

Paul

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Been searching for this for a good half hour.. So much mis-information surrounding this simple line.. – Partack Jun 21 '14 at 03:56
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For a perfect Unix timestamp without the milliseconds, do this: var milliseconds = Math.floor((new Date).getTime()/1000); – Geek Stocks Dec 09 '14 at 11:29
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Does this account for leap seconds? – Ray Suelzer Mar 29 '15 at 16:29
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@RaySuelzer It gets the time according the the system clock of the machine its running on, so it depends entirely on that. – Paul Apr 15 '15 at 18:12
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Should it be var milliseconds = (new Date()).getTime(); ? Notice the 2 parentheses after Date. – Guillaume Renoult Jul 08 '15 at 01:11
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@grenoult That means the same thing in Javascript. You only need parenthesis when passing arguments to a constructor. `((new Date())`, `new Date()`, and `(new Date)` would all work in this case. Use whichever you find the most readable. – Paul Jul 08 '15 at 14:58
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@GeekStocks thnx a lot!!!! – ReyAnthonyRenacia May 15 '16 at 22:15
@RaySuelzer Unix time does not account for leap seconds. For more information read the wikipedia entry on Unix time. – Himerzi Aug 23 '16 at 17:17
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var milliseconds = +new Date; – Cleber Dantas Feb 15 '17 at 22:08
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`Date.now()` https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/now – Bradley Apr 06 '18 at 15:38
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Good answer! Note: If you want the milliseconds at two different points in a program, you need to create the (new Date) object at each point, and you cannot use the same one. – HoldOffHunger Jun 01 '18 at 15:21
For milliseconds use return new Date() / 1; – Mitzi Feb 04 '21 at 17:48

score 85 · Answer 2 · edited Mar 28 '20 at 13:43

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This will do the trick :-

new Date().valueOf()

edited Mar 28 '20 at 13:43

Sangwin Gawande

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answered Mar 05 '12 at 23:40

raina77ow

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Did you get the parenthesis wrong? Check out this (rejected) [edit suggestion](http://stackoverflow.com/review/suggested-edits/14668514) from MarkHu. – Nisse Engström Dec 22 '16 at 04:33
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No, it's working; you can check [this great answer](http://stackoverflow.com/a/36597316/1229023) explaining the reasons. BTW, this expression can be simplified up to `+new Date` - for the same reasons. – raina77ow Dec 22 '16 at 21:43
This would bomb out in php where you would need to do `(new DateTime)->format('U')` but js is ok without the parens – chiliNUT Aug 29 '17 at 02:38

How to get time in milliseconds since the unix epoch in Javascript?

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