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I need to convert 04/06/13 (for example) to a long date - Tue Jun 04 2013 00:00:00 GMT+0100 (BST). How can I do this using Javascript? I know how to convert a long date to a short date - just not the other way round.

Matt Kantor
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James Anderson
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4 Answers4

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You could try the parsing functionality of the Date constructor, whose result you then can stringify:

> new Date("04/06/13").toString()
"Sun Apr 06 1913 00:00:00 GMT+0200" // or something

But the parsing is implementation-dependent, and there won't be many engines that interpret your odd DD/MM/YY format correctly. If you had used MM/DD/YYYY, it probably would be recognized everywhere.

Instead, you want to ensure how it is parsed, so have to do it yourself and feed the single parts into the constructor:

var parts = "04/06/13".split("/"),
    date = new Date(+parts[2]+2000, parts[1]-1, +parts[0]);
console.log(date.toString()); // Tue Jun 04 2013 00:00:00 GMT+0200
Bergi
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  • That's strange, because on Chrome v25 "new Date("04/06/13")" evaluates to "Sat Apr 06 2013 00:00:00 GMT+0200 (CEST)" – Xotic750 May 18 '13 at 18:19
  • Why is that strange? Date parsing is implementation-dependent by spec, it only needs to recognize ISO8601 and its own `toString` output. I would even have *expected* an odd format like `DD/MM/YY` not to be parsed correctly everywhere. – Bergi May 18 '13 at 18:23
  • I thought that all implementations defaulted to 1900. Hence it was strange or a shock for me to see that this was not the case. – Xotic750 May 18 '13 at 18:26
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    *don't* use the parsing functionality - it's locale dependent! Always use the latter form where you pass the year, month and date as numbers. – Alnitak May 18 '13 at 19:03
  • @Alnitak: Yeah, seems I didn't emphazise this enough. Answer updated :-) – Bergi May 18 '13 at 20:52
  • Works perfectly, thanks! How can I convert this long date back to a short date now? – James Anderson May 19 '13 at 09:28
  • You will need to manually construct it again (or use a [library](http://stackoverflow.com/a/12632212/1048572)). `Date` objects have useful methods, look into them! – Bergi May 19 '13 at 09:34
  • I've had a look around and can't find anything that will work. I'm trying to use http://momentjs.com for example, and I can't seem to be able to convert the long date to a short one? – James Anderson May 19 '13 at 09:49
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    @Bergi NB: `dd/mm/yy` is _not_ an odd format - it's used by most of the world and it's a damn sight more logical than the US `mm/dd/yy` format! – Alnitak May 19 '13 at 11:10
  • @Alnitak: `dd/mm/yyyy` is OK. Yet the confusion with the really odd US format does make it not well-suited for exchanging dates - especially since browsers are not consistent there (and seem to favour the US format). Better would be the international standard `yyyy-mm-dd`. – Bergi May 19 '13 at 20:00
  • @Bergi oh, absolutely, everyone should really be using ISO 8601 :) – Alnitak May 19 '13 at 20:18
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An alternative to the split method, uses lastIndexof and slice instead, to change the year to ISO8601 format which then gives a non-standard string that is known to be working across browsers, and then uses the date parsing method. (assuming a fixed pattern like in question)

However,

If you want to ensure how it is parsed, you have to do it yourself and feed the single parts into the constructor:

, this would mean using the split method, see @Bergi answer.

var string = "04/06/13",
    index = string.lastIndexOf("/") + 1,
    date = new Date(string.slice(0, index) +  (2000 + parseInt(string.slice(index), 10)));

console.log(date);

Output

Sat Apr 06 2013 00:00:00 GMT+0200 (CEST)

On jsfiddle

or a further alternative would be to use moments.js

var string = "04/06/13";

console.log(moment(string, "DD/MM/YY").toString());

Output

Sat Apr 06 2013 00:00:00 GMT+0200 (CEST)

On jsfiddle

Community
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Xotic750
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    `"04/06/2013"` is not [ISO 8601](http://en.wikipedia.org/wiki/ISO_8601) - though the format is known to be working across browsers. – Bergi May 18 '13 at 18:50
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    +1 for Moment.js. Most reliable way to do this consistently across browsers that I know of. – Matt Johnson-Pint May 19 '13 at 03:29
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You can use:

new Date(2013, 06, 04)

...or directly using a date string (i.e. a string representing a date as accepted by the parse method):

new Date("2013/06/04");

...or by specifying the different parts of your date, like:

new Date(year, month, day [, hour, minute, second, millisecond]);

Take a look at this.

excentris
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You have to take 13 as 2013 otherwise it will take default 1913

alert(new Date('04/06/2013'));
Manish Jangir
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