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Incorrect date shown in new Date() in JavaScript

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);

How to create a javascript date from 12 hour format

How can I create a Date object from a date with this format:
03/23/2016 02:00:00 PM

The Date object can parse strings: new Date('03/23/2016 02:00:00 PM')
For example:
var date = new Date('03/23/2016 02:00:00 PM') // => "Wed Mar 23 2016 14:00:00 GMT-0700 (PDT)"
date.getFullYear() // => 2016
However, I would recommend using a library that someone else has already spent time considering the edge cases, like time zones, etc. (a good one I've used is moment.js).
Keep in mind (from the moment.js docs):
Warning: Browser support for parsing strings is inconsistent. Because there is no specification on which formats should be supported, what works in some browsers will not work in other browsers.
For consistent results parsing anything other than ISO 8601 strings, you should use String + Format.

var date = new Date("3/23/2016 02:00:00 PM");
console.log(date);
You can then access all the methods of the Date object.

Looking at MDN
var date = new Date('03/23/2016 02:00:00 PM')

You can use something like date.js:
First use script, then write date:
<script type="text/javascript" src="http://www.datejs.com/build/date.js"></script>
....
document.write(new Date().toString("dd:MM:yyyy hh:mm:ss tt"));

Wrong date with angular material's date picker

I use the datepicker to pick a date and send it to the server.
When I log the JS value I get the correct result:
Tue Mar 22 2016 00:00:00 GMT+0100 (Mitteleuropäische Zeit)
but in the ajax request it is
2016-03-21T23:00:00.000Z
I don't modify the values, just giving the object to angulars http function.
Does Angular need some configuration to handle it?

You can try the following piece of code
dateObj.setMinutes((dateObj.getMinutes() + dateObj.getTimezoneOffset()));
No need of localization, use this code just before doing any service call. It will pass you the exact date what you selected in the datepicker.
It will work in all timezone (+) and (-),
Example: 2016-03-21 00:00:00 GMT+0100, the above said code covert it as 2016-03-21 01:00:00 GMT+0000. While on Service it converts it as 2016-03-21 00:00:00.
I think it will solve your problem.

Those two strings represent the same time. One is in UTC, i.e. GMT +0, which you can see from the Z ending. The other is in a different timezone, specifically GMT +1 hour.
If you had javascript date objects for both strings, and turned them into integers, i.e. seconds passed since Jan 1, 1970, UTC, you'd find them identical. They represent the same instant but in two different geographic locations.
var d1 = new Date('Tue Mar 22 2016 00:00:00 GMT+0100');
var d2 = new Date('2016-03-21T23:00:00.000Z');
Number(d1); // 1458601200000
Number(d2); // 1458601200000
Generally this is a good thing. Dealing in timezones gets very confusing. I find it best for a server to always deal in UTC.

https://github.com/angular/material/pull/9410
Check out the 1.1.1+ version. This will solve your issue.
<md-datepicker ng-model="date" ng-model-options="{ timezone: 'utc' }"></md-datepicker>

If suppose am selecting a date like Tue Aug 06 2019 00:00:00 GMT+0530 (India Standard Time), am getting 2019-08-05T18:30:00.000Z. ( which in my case previous date with respect to the selected date)
I made use of toLocalDateString() to do the job.
// this.date = 2019-08-05T18:30:00.000Z
const converted = new Date(this.date).toLocaleDateString();
console.log(converted); // 8/6/2019 (MM/DD/YYYY) format

Date is invalid in IE and Firefox but is chrome it works fine

var stdate=document.forms["myForm"]["from"].value;
var endate=document.forms["myForm"]["to"].value;
var fromDate = new Date(stdate);
var toDate = new Date(endate);
alert(fromDate);
Input:
from: 19-Mar-2014 03:13:50 PM
Output: (in IE & Firefox)
invalid Date
in Chrome broswer:
Wed Mar 19 2014 15:13:50 GMT-0400 (Eastern Daylight Time)
What date format should I use so that all browsers support? Or how should I handle it?

In most cases, new Date(datestring) is all you need. But you need to chose the format carefully.
Here's a nice compatibility table: http://dygraphs.com/date-formats.html
The short version is this:
Dates only? use YYYY/mm/DD; never use hyphens in this format
Need time, but local time is OK? use YYYY/mm/DD HH:MM:SS; again, no hyphens
OK to ignore IE<9? Consider using ISO8601 with whole seconds (YYYY-mm-DDTHH:MM:SSZ, or with time-zone)
Need a UTC time in IE8? You'll have to do something clever. Xotic's answer looks good here.

As documented on MSDN (IE) - the Date constructor supports either a timestamp or a Datestring in a Format supported by Date.parse. According to the docs this is either RFC2822 or ISO 8601. some examples: 2011-10-10 or Mon, 25 Dec 1995 13:30:00 GMT should be valid arguments.

I would use an ISO8601
formatted string in UTC as my input, but then manually
split
this string into parts and feed them into my
Date
constructor thus avoiding date parsing issues.
Example
var iso8601 = '2014-03-19T03:13:50.000Z',
parts = iso8601.slice(0, -1).split(/[\-T:]/),
dateObject;
parts[1] -= 1;
dateObject = new Date(Date.UTC.apply(undefined, parts));
console.log(dateObject.toUTCString());
Output
Wed, 19 Mar 2014 03:13:50 GMT
On jsFiddle

Inconsistencies when creating new date objects

I am creating new date objects in javascript and seeing some inconsistencies depending on whether I use the dateString parameter vs the year/month/day integer parameters.
Here's an example:
var dt1 = new Date(1979,3,5);
var dt2 = new Date('1979-04-05');
jsFiddle with example
dt1 is assigned the value: Thu Apr 05 1979 00:00:00 GMT-0500 (Central Daylight Time)
dt2 is assigned the value: Wed Apr 04 1979 19:00:00 GMT-0500 (Central Daylight Time)
Can someone explain this behavior? The second example (dt2) happens to be the format that Chrome is returning a selected date from input[type=date] elements which is why I'm trying to figure this out.

It looks like the form '1979-04-05' is interpreted as a UTC date (and then that UTC date is converted to local time when displayed). The form new Date(1979,3,5); is interpreted as local time. You can use Date.UTC to force UTC time for the 3-argument form (see docs).
Date parsing (and timezone handling in particular) is generally not uniform across browsers, and it's better not to depend on it - use UTC whenever possible, or use a separate library like Date.js or moment.js.