How to format a JavaScript date

Use the date.format library:

var dateFormat = require('dateformat');
var now = new Date();
dateFormat(now, "dddd, mmmm dS, yyyy, h:MM:ss TT");

returns:

Saturday, June 9th, 2007, 5:46:21 PM 

dateformat on npm

http://jsfiddle.net/phZr7/1/

If you need to quickly format your date using plain JavaScript, use getDate, getMonth + 1, getFullYear, getHours and getMinutes:

var d = new Date();

var datestring = d.getDate()  + "-" + (d.getMonth()+1) + "-" + d.getFullYear() + " " +
d.getHours() + ":" + d.getMinutes();

// 16-5-2015 9:50

Or, if you need it to be padded with zeros:

var datestring = ("0" + d.getDate()).slice(-2) + "-" + ("0"+(d.getMonth()+1)).slice(-2) + "-" +
    d.getFullYear() + " " + ("0" + d.getHours()).slice(-2) + ":" + ("0" + d.getMinutes()).slice(-2);

// 16-05-2015 09:50

Well, what I wanted was to convert today's date to a MySQL friendly date string like 2012-06-23, and to use that string as a parameter in one of my queries. The simple solution I've found is this:

var today = new Date().toISOString().slice(0, 10);

Keep in mind that the above solution does not take into account your timezone offset.

You might consider using this function instead:

function toJSONLocal (date) {
    var local = new Date(date);
    local.setMinutes(date.getMinutes() - date.getTimezoneOffset());
    return local.toJSON().slice(0, 10);
}

This will give you the correct date in case you are executing this code around the start/end of the day.

• Example: http://jsfiddle.net/simo/sapuhzmm/
• Date.toISOString
• Date.toJSON
• String.slice

Custom formatting function:

For fixed formats, a simple function make the job. The following example generates the international format YYYY-MM-DD:

function dateToYMD(date) {
    var d = date.getDate();
    var m = date.getMonth() + 1; //Month from 0 to 11
    var y = date.getFullYear();
    return '' + y + '-' + (m<=9 ? '0' + m : m) + '-' + (d <= 9 ? '0' + d : d);
}

console.log(dateToYMD(new Date(2017,10,5))); // Nov 5

The OP format may be generated like:

function dateToYMD(date) {
    var strArray=['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
    var d = date.getDate();
    var m = strArray[date.getMonth()];
    var y = date.getFullYear();
    return '' + (d <= 9 ? '0' + d : d) + '-' + m + '-' + y;
}
console.log(dateToYMD(new Date(2017,10,5))); // Nov 5

Note: It is, however, usually not a good idea to extend the JavaScript standard libraries (e.g. by adding this function to the prototype of Date).

A more advanced function could generate configurable output based on a format parameter.

If to write a formatting function is too long, there are plenty of libraries around which does it. Some other answers already enumerate them. But increasing dependencies also has it counter-part.

Standard ECMAScript formatting functions:

Since more recent versions of ECMAScript, the Date class has some specific formatting functions:

toDateString: Implementation dependent, show only the date.

http://www.ecma-international.org/ecma-262/7.0/index.html#sec-date.prototype.todatestring

new Date().toDateString(); // e.g. "Fri Nov 11 2016"

toISOString: Show ISO 8601 date and time.

http://www.ecma-international.org/ecma-262/7.0/index.html#sec-date.prototype.toisostring

new Date().toISOString(); // e.g. "2016-11-21T08:00:00.000Z"

toJSON: Stringifier for JSON.

http://www.ecma-international.org/ecma-262/7.0/index.html#sec-date.prototype.tojson

new Date().toJSON(); // e.g. "2016-11-21T08:00:00.000Z"

toLocaleDateString: Implementation dependent, a date in locale format.

http://www.ecma-international.org/ecma-262/7.0/index.html#sec-date.prototype.tolocaledatestring

new Date().toLocaleDateString(); // e.g. "21/11/2016"

toLocaleString: Implementation dependent, a date&time in locale format.

http://www.ecma-international.org/ecma-262/7.0/index.html#sec-date.prototype.tolocalestring

new Date().toLocaleString(); // e.g. "21/11/2016, 08:00:00 AM"

toLocaleTimeString: Implementation dependent, a time in locale format.

http://www.ecma-international.org/ecma-262/7.0/index.html#sec-date.prototype.tolocaletimestring

new Date().toLocaleTimeString(); // e.g. "08:00:00 AM"

toString: Generic toString for Date.

http://www.ecma-international.org/ecma-262/7.0/index.html#sec-date.prototype.tostring

new Date().toString(); // e.g. "Fri Nov 21 2016 08:00:00 GMT+0100 (W. Europe Standard Time)"

Note: it is possible to generate custom output out of those formatting >

new Date().toISOString().slice(0,10); //return YYYY-MM-DD

Examples snippets:

console.log("1) "+  new Date().toDateString());
console.log("2) "+  new Date().toISOString());
console.log("3) "+  new Date().toJSON());
console.log("4) "+  new Date().toLocaleDateString());
console.log("5) "+  new Date().toLocaleString());
console.log("6) "+  new Date().toLocaleTimeString());
console.log("7) "+  new Date().toString());
console.log("8) "+  new Date().toISOString().slice(0,10));

If you are already using jQuery UI in your project you could do it this way:

var formatted = $.datepicker.formatDate("M d, yy", new Date("2014-07-08T09:02:21.377"));

// formatted will be 'Jul 8, 2014'

Some datepicker date format options to play with are available here.