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Javascript Date constructor depending by timezone [duplicate]

This is what I get in chrome console. I pass "2016-09-05"(YYYY-MM-DD) as the date and it shows me Sept 4,2016 as the date.
Another constructor shows the right date
Passing it comma separated needs some tokenizing + parsing + making month zero indexed which I want to avoid

If you omit the time in the new Date(string) constructor, UTC time is assumed. So the displayed value is actually correct. Use new Date('2016-09-05T00:00') to create the date object in local time.
Edit: while some browsers seem to support the yyyy-MM-dd HH:mm format, it's not officially supported, and, as mentioned in the comments, this doesn't work in Safari. I've updated the answer to use a T instead of a space between date and time.
Per the ECMAScript® 2023 Language Specification:
Date-only forms:
YYYY
YYYY-MM
YYYY-MM-DD
It also includes “date-time” forms that consist of one of the above
date-only forms immediately followed by one of the following time
forms with an optional UTC offset representation appended:
THH:mm
THH:mm:ss
THH:mm:ss.sss

You could use the Solution from UTC Date Conversion.
Which basicall does the following:
console.log(new Date("2014-12-23"));
console.log(convertDateToUTC(new Date("2014-12-23")));
function convertDateToUTC(date) {
return new Date(date.getUTCFullYear(), date.getUTCMonth(), date.getUTCDate(), date.getUTCHours(), date.getUTCMinutes(), date.getUTCSeconds());
}
The output would be like that in the console (for me at least :D)
Tue Dec 23 2014 01:00:00 GMT+0100 (Mitteleuropäische Zeit)
Tue Dec 23 2014 00:00:00 GMT+0100 (Mitteleuropäische Zeit)

use setFullYear the syntax is Date.setFullYear(year,month,day)
mydate = new Date();
mydate.setFullYear(2016, 08, 05);

What format do I use with moment to give me same string as `new Date()`?

I'm using moment() and want to know if there's a shortcut to give me the same date string as new Date() would give me.
I have to do some timezone conversions so using moment.js makes that easier, but I need the same date format: Thu Oct 06 2016 23:08:53 GMT-0700 (PDT) as the native Date object would give me.
I would assume there is a shortcut for this, but I can't find it.
moment.tz('America/New_York').format('???')

I could not find a shortcut however this gives the string I need:
moment.tz('America/New_York').format('ddd MMM DD YYYY HH:mm:ss [GMT]ZZ (z)')
from the docs: http://momentjs.com/docs/#/displaying/
Returns: Fri Oct 07 2016 02:25:17 GMT-0400 (EDT)

if you have no idea which timezone the browser is currently in, you can try moment.tz.guess(), it isn't 100% correct for timezone offset that has multiple names though:
var d = moment()._d;
d.toString().replace(/\([\w ]+\)$/, moment.tz(d, moment.tz.guess()).format('(z)'));

The date format you're referring to, depends on the culture/language of your browser. That aside, if you want the same format as the standard new Date().toString() returns, you just use the toString() method on the moment object, without any arguments:
moment().toString();
Source: http://momentjs.com/docs/#/displaying/as-string/

Javascript New Date Changing Hour Value

I am receiving times in the an AJAX request and am converting them using the new Date() function.
I receive 2013-06-18T12:00:15Z
However, somehow I get the following after new Date():
Tue Jun 18 2013 08:00:15 GMT-0400 (EDT)
Why is it not:
Tue Jun 18 2013 12:00
See the following demo:
http://www.w3schools.com/js/tryit.asp?filename=tryjs_date_convert

This is a time zone problem. You must be in the EDT timezone (GMT-0400). To correctly parse the date you should tell the parser in which timezone your date is correct.
For you parse your date like this :
new Date('2013-06-18 12:00:15 GMT-0400')
"GMT-0400" means GMT time minus 4 hours
Or if you don't wish to reformat your string, you can use the date.getUTC* functions to get the time as you parsed it.
The full list is available at Mozilla's documentation.

I agree with Vaim Caen's answer that this is a timezone issue, but not with parsing - the date is being parsed fine, but into your local timezone, while you're expecting it to be parsed into UTC date.
This answer shows how to convert from your current timezone to UTC - applying this to the TryIt demo gives:
var msec = Date.parse("2013-06-18T12:00:15Z");
// or: var msec = Date.parse("Tue Jun 18 2013 08:00:15 GMT-0400 (EDT)");
var d = new Date(msec);
d.setTime( d.getTime() + d.getTimezoneOffset()*60*1000 );
document.getElementById("demo").innerHTML = d;
Edit: If you all you're interested in is displaying the date (no further manipulations) then you can use:
d.toUTCString()
which will show the date in GMT (for me it actually shows "GMT" so most likely not of use!)
The alternative is to add a function to the prototype to show the date in whatever format you want and use the date.getUTC* methods.

Why does moment.js return this date wrong?

I'm simply trying to take an input string and convert it to a date object.
moment.utc('2000-01-01T00:00:00.000Z').toDate()
But it returns this...
Fri Dec 31 1999 19:00:00 GMT-0500 (EST)
Thanks

That is a valid JavaScript Date Object. You can test this by opening a console in Chrome or Firefox, then entering the following:
// Mon Nov 24 2014 09:54:00 GMT-0800 (PST) (looks the same as your example)
console.log( new Date() );
If you want to format the value coming out of moment.js, you can use its format method and a mask.
// Example: November 24th 2014, 09:58:12am
var fdate = moment().format('MMMM Do YYYY, h:mm:ss a');
Moment.js doesn't modify the prototype, it simply wraps it.
If you want to convert a string to a date object using moment.js, you can just call it as such:
moment(your_date); // Unless in UTC mode this will display as local time
In your instance you're using the UTC mode.

2000-01-01T00:00:00.000Z is the GMT date/time.
Using moment.utc("2000-01-01T00:00:00.000Z").toDate() returns this date/time according to your timzone settings.
See : http://www.digitoffee.com/programming/get-local-time-utc-using-moment-js/94/
Hope it helps.

Converting Javascript Date

I have a date String in this format: Tue Sep 02 00:00:00 GMT+200 2014, I'd like to have only in Javascript this ISO Format: 2014-09-02T00:00:00.000Z.
So I have wrote this code:
var date = new Date("Tue Sep 02 00:00:00 GMT+200 2014");
date.toJSON();
but it returns: "2014-09-01T22:00:00.000Z".
How can I have the right date in ISO format? Thank you.

If you want to use the JavaScript native Date Object, you may want to look at its documentation first, especially the toISOString() method.
var date = new Date("Tue Sep 02 00:00:00 GMT+200 2014");
var n = date.toISOString();
this returns:
n: '2014-09-01T22:00:00.000Z'
which is the right ISO format. Your initial time is GMT+2 so, in ISO time, it corresponds to the same date/time but two hours before. As it is the 2nd of Sept, 00:00:00, 2 hours before lead to the day before, the 1st of Sept, at 22:00:00. You can't have the 2014-09-02T00:00:00.000Z you want in your question because it is not corresponding to an ISO date.
You can read more about ISO 8601 on Wikipedia.

There is a method for that.
date.toISOString()