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How to convert a date dd/mm/yyyy into the date object format [duplicate]

I want to convert date to timestamp, my input is 26-02-2012. I used
new Date(myDate).getTime();
It says NaN.. Can any one tell how to convert this?

Split the string into its parts and provide them directly to the Date constructor:
Update:
var myDate = "26-02-2012";
myDate = myDate.split("-");
var newDate = new Date( myDate[2], myDate[1] - 1, myDate[0]);
console.log(newDate.getTime());

Try this function, it uses the Date.parse() method and doesn't require any custom logic:
function toTimestamp(strDate){
var datum = Date.parse(strDate);
return datum/1000;
}
alert(toTimestamp('02/13/2009 23:31:30'));

this refactored code will do it
let toTimestamp = strDate => Date.parse(strDate)
this works on all modern browsers except ie8-

There are two problems here.
First, you can only call getTime on an instance of the date. You need to wrap new Date in brackets or assign it to variable.
Second, you need to pass it a string in a proper format.
Working example:
(new Date("2012-02-26")).getTime();

UPDATE: In case you came here looking for current timestamp
Date.now(); //as suggested by Wilt
or
var date = new Date();
var timestamp = date.getTime();
or simply
new Date().getTime();
/* console.log(new Date().getTime()); */

You need just to reverse your date digit and change - with ,:
new Date(2012,01,26).getTime(); // 02 becomes 01 because getMonth() method returns the month (from 0 to 11)
In your case:
var myDate="26-02-2012";
myDate=myDate.split("-");
new Date(parseInt(myDate[2], 10), parseInt(myDate[1], 10) - 1 , parseInt(myDate[0]), 10).getTime();
P.S. UK locale does not matter here.

To convert (ISO) date to Unix timestamp, I ended up with a timestamp 3 characters longer than needed so my year was somewhere around 50k...
I had to devide it by 1000:
new Date('2012-02-26').getTime() / 1000

function getTimeStamp() {
var now = new Date();
return ((now.getMonth() + 1) + '/' + (now.getDate()) + '/' + now.getFullYear() + " " + now.getHours() + ':'
+ ((now.getMinutes() < 10) ? ("0" + now.getMinutes()) : (now.getMinutes())) + ':' + ((now.getSeconds() < 10) ? ("0" + now
.getSeconds()) : (now.getSeconds())));
}

For those who wants to have readable timestamp in format of, yyyymmddHHMMSS
> (new Date()).toISOString().replace(/[^\d]/g,'') // "20190220044724404"
> (new Date()).toISOString().replace(/[^\d]/g,'').slice(0, -3) // "20190220044724"
> (new Date()).toISOString().replace(/[^\d]/g,'').slice(0, -9) // "20190220"
Usage example: a backup file extension. /my/path/my.file.js.20190220

Your string isn't in a format that the Date object is specified to handle. You'll have to parse it yourself, use a date parsing library like MomentJS or the older (and not currently maintained, as far as I can tell) DateJS, or massage it into the correct format (e.g., 2012-02-29) before asking Date to parse it.
Why you're getting NaN: When you ask new Date(...) to handle an invalid string, it returns a Date object which is set to an invalid date (new Date("29-02-2012").toString() returns "Invalid date"). Calling getTime() on a date object in this state returns NaN.

JUST A REMINDER
Date.parse("2022-08-04T04:02:10.909Z")
1659585730909
Date.parse(new Date("2022-08-04T04:02:10.909Z"))
1659585730000

/**
* Date to timestamp
* #param string template
* #param string date
* #return string
* #example datetotime("d-m-Y", "26-02-2012") return 1330207200000
*/
function datetotime(template, date){
date = date.split( template[1] );
template = template.split( template[1] );
date = date[ template.indexOf('m') ]
+ "/" + date[ template.indexOf('d') ]
+ "/" + date[ template.indexOf('Y') ];
return (new Date(date).getTime());
}

The below code will convert the current date into the timestamp.
var currentTimeStamp = Date.parse(new Date());
console.log(currentTimeStamp);

The first answer is fine however Using react typescript would complain because of split('')
for me the method tha worked better was.
parseInt((new Date("2021-07-22").getTime() / 1000).toFixed(0))
Happy to help.

In some cases, it appears that some dates are stubborn, that is, even with a date format, like "2022-06-29 15:16:21", you still get null or NaN. I got to resolve mine by including a "T" in the empty space, that is:
const inputDate = "2022-06-29 15:16:21";
const newInputDate = inputDate.replace(" ", "T");
const timeStamp = new Date(newInputDate).getTime();
And this worked fine for me! Cheers!

It should have been in this standard date format YYYY-MM-DD, to use below equation. You may have time along with example: 2020-04-24 16:51:56 or 2020-04-24T16:51:56+05:30. It will work fine but date format should like this YYYY-MM-DD only.
var myDate = "2020-04-24";
var timestamp = +new Date(myDate)

You can use valueOf method
new Date().valueOf()

a picture speaks a thousand words :)
Here I am converting the current date to timestamp and then I take the timestamp and convert it to the current date back, with us showing how to convert date to timestamp and timestamp to date.

The simplest and accurate way would be to add the unary operator before the date
console.log(`Time stamp is: ${Number(+new Date())}`)

Answers have been provided by other developers but in my own way, you can do this on the fly without creating any user defined function as follows:
var timestamp = Date.parse("26-02-2012".split('-').reverse().join('-'));
alert(timestamp); // returns 1330214400000

Simply performing some arithmetic on a Date object will return the timestamp as a number. This is useful for compact notation. I find this is the easiest way to remember, as the method also works for converting numbers cast as string types back to number types.
let d = new Date();
console.log(d, d * 1);

This would do the trick if you need to add time also
new Date('2021-07-22 07:47:05.842442+00').getTime()
This would also work without Time
new Date('2021-07-22 07:47:05.842442+00').getTime()
This would also work but it won't Accept Time
new Date('2021/07/22').getTime()
And Lastly if all did not work use this
new Date(year, month, day, hours, minutes, seconds, milliseconds)
Note for Month it the count starts at 0 so Jan === 0 and Dec === 11

+new Date(myDate)
this should convert myDate to timeStamp

How to get LocaleTime without seconds in javascript?

i have a timestamp which is for example '2013-01-21T01:23:44'
i am doing this to get the time
var time1= new Date('2013-01-21T01:23:44');
var time2 = time1.toLocaleTimeString();
This is returning the time but as 01:23:44 . How do i do this in a way it does not return the seconds .

What about trimming it off using regex?
time2 = time1.toLocaleTimeString().replace(/(.*)\D\d+/, '$1');

This sometimes wont work, see RobG answer instead.
remove the last 3 characters:
str = str.slice(0, -3);

> var time1= new Date('2013-01-21T01:23:44');
Until ES5, parsing of strings by the Date constructor was entirely implementation dependent. Subsequent to ES5, there are 3 formats that are supported (the formats produced by Date.prototype.toString, toISOString and toUTCString) but everything else is still implementation dependent.
Timestamps in the format YYYY-MM-DDTHH:mm:ss without an offset should be parsed as local, but there may be non–conforming implementations in use.
One solution is to parse it to a Date then format the time as required.
The localeTimeString function is implementation dependent and results vary depending on system settings. It's intended to represent a time that is tailored for particular users, so you should not mess with it as you can't be certain of its format (and it's supposed to be something the user will understand, not somethign you think they will understand).
The following uses a couple of small functions to parse the timestamp to a Date then format the time as required.
// Parse timestamp in YYYY-MM-DDTHH:mm:ss format as local
function parseDateString(s) {
var b = s.split(/\D/g);
return new Date(b[0], --b[1], b[2], b[3], b[4], b[5], 0);
}
// Format time as hh:mm AM/PM
function formatHHMM(date) {
function z(n) {
return (n < 10 ? '0' : '') + n;
}
var h = date.getHours();
return z(h % 12 || 12) + ':' + z(date.getMinutes()) + ' ' + (h < 12 ? 'AM' : 'PM');
}
console.log(
formatHHMM(parseDateString('2013-01-21T00:23:44')) // 12:23 AM
);
your result may differ, it depends on your timezone as the string is treated as UTC.

I don't know if you would like to work with an additional library but momentjs is awesome for date and time formats. You can find the site here: http://momentjs.com/
You can simply change the format like
var time1 = moment().format("hh:mm")

You can set the timeStyle to short.
var time1 = new Date('2013-01-21T01:23:44');
var time2 = time1.toLocaleTimeString(undefined, {timeStyle:'short'}); //1:23 AM

How to convert date to timestamp?

I want to convert date to timestamp, my input is 26-02-2012. I used
new Date(myDate).getTime();
It says NaN.. Can any one tell how to convert this?

Split the string into its parts and provide them directly to the Date constructor:
Update:
var myDate = "26-02-2012";
myDate = myDate.split("-");
var newDate = new Date( myDate[2], myDate[1] - 1, myDate[0]);
console.log(newDate.getTime());

Try this function, it uses the Date.parse() method and doesn't require any custom logic:
function toTimestamp(strDate){
var datum = Date.parse(strDate);
return datum/1000;
}
alert(toTimestamp('02/13/2009 23:31:30'));

this refactored code will do it
let toTimestamp = strDate => Date.parse(strDate)
this works on all modern browsers except ie8-

There are two problems here.
First, you can only call getTime on an instance of the date. You need to wrap new Date in brackets or assign it to variable.
Second, you need to pass it a string in a proper format.
Working example:
(new Date("2012-02-26")).getTime();

UPDATE: In case you came here looking for current timestamp
Date.now(); //as suggested by Wilt
or
var date = new Date();
var timestamp = date.getTime();
or simply
new Date().getTime();
/* console.log(new Date().getTime()); */

You need just to reverse your date digit and change - with ,:
new Date(2012,01,26).getTime(); // 02 becomes 01 because getMonth() method returns the month (from 0 to 11)
In your case:
var myDate="26-02-2012";
myDate=myDate.split("-");
new Date(parseInt(myDate[2], 10), parseInt(myDate[1], 10) - 1 , parseInt(myDate[0]), 10).getTime();
P.S. UK locale does not matter here.

To convert (ISO) date to Unix timestamp, I ended up with a timestamp 3 characters longer than needed so my year was somewhere around 50k...
I had to devide it by 1000:
new Date('2012-02-26').getTime() / 1000

function getTimeStamp() {
var now = new Date();
return ((now.getMonth() + 1) + '/' + (now.getDate()) + '/' + now.getFullYear() + " " + now.getHours() + ':'
+ ((now.getMinutes() < 10) ? ("0" + now.getMinutes()) : (now.getMinutes())) + ':' + ((now.getSeconds() < 10) ? ("0" + now
.getSeconds()) : (now.getSeconds())));
}

For those who wants to have readable timestamp in format of, yyyymmddHHMMSS
> (new Date()).toISOString().replace(/[^\d]/g,'') // "20190220044724404"
> (new Date()).toISOString().replace(/[^\d]/g,'').slice(0, -3) // "20190220044724"
> (new Date()).toISOString().replace(/[^\d]/g,'').slice(0, -9) // "20190220"
Usage example: a backup file extension. /my/path/my.file.js.20190220

Your string isn't in a format that the Date object is specified to handle. You'll have to parse it yourself, use a date parsing library like MomentJS or the older (and not currently maintained, as far as I can tell) DateJS, or massage it into the correct format (e.g., 2012-02-29) before asking Date to parse it.
Why you're getting NaN: When you ask new Date(...) to handle an invalid string, it returns a Date object which is set to an invalid date (new Date("29-02-2012").toString() returns "Invalid date"). Calling getTime() on a date object in this state returns NaN.

JUST A REMINDER
Date.parse("2022-08-04T04:02:10.909Z")
1659585730909
Date.parse(new Date("2022-08-04T04:02:10.909Z"))
1659585730000

/**
* Date to timestamp
* #param string template
* #param string date
* #return string
* #example datetotime("d-m-Y", "26-02-2012") return 1330207200000
*/
function datetotime(template, date){
date = date.split( template[1] );
template = template.split( template[1] );
date = date[ template.indexOf('m') ]
+ "/" + date[ template.indexOf('d') ]
+ "/" + date[ template.indexOf('Y') ];
return (new Date(date).getTime());
}

The below code will convert the current date into the timestamp.
var currentTimeStamp = Date.parse(new Date());
console.log(currentTimeStamp);

The first answer is fine however Using react typescript would complain because of split('')
for me the method tha worked better was.
parseInt((new Date("2021-07-22").getTime() / 1000).toFixed(0))
Happy to help.

In some cases, it appears that some dates are stubborn, that is, even with a date format, like "2022-06-29 15:16:21", you still get null or NaN. I got to resolve mine by including a "T" in the empty space, that is:
const inputDate = "2022-06-29 15:16:21";
const newInputDate = inputDate.replace(" ", "T");
const timeStamp = new Date(newInputDate).getTime();
And this worked fine for me! Cheers!

It should have been in this standard date format YYYY-MM-DD, to use below equation. You may have time along with example: 2020-04-24 16:51:56 or 2020-04-24T16:51:56+05:30. It will work fine but date format should like this YYYY-MM-DD only.
var myDate = "2020-04-24";
var timestamp = +new Date(myDate)

You can use valueOf method
new Date().valueOf()

a picture speaks a thousand words :)
Here I am converting the current date to timestamp and then I take the timestamp and convert it to the current date back, with us showing how to convert date to timestamp and timestamp to date.

The simplest and accurate way would be to add the unary operator before the date
console.log(`Time stamp is: ${Number(+new Date())}`)

Answers have been provided by other developers but in my own way, you can do this on the fly without creating any user defined function as follows:
var timestamp = Date.parse("26-02-2012".split('-').reverse().join('-'));
alert(timestamp); // returns 1330214400000

Simply performing some arithmetic on a Date object will return the timestamp as a number. This is useful for compact notation. I find this is the easiest way to remember, as the method also works for converting numbers cast as string types back to number types.
let d = new Date();
console.log(d, d * 1);

This would do the trick if you need to add time also
new Date('2021-07-22 07:47:05.842442+00').getTime()
This would also work without Time
new Date('2021-07-22 07:47:05.842442+00').getTime()
This would also work but it won't Accept Time
new Date('2021/07/22').getTime()
And Lastly if all did not work use this
new Date(year, month, day, hours, minutes, seconds, milliseconds)
Note for Month it the count starts at 0 so Jan === 0 and Dec === 11

+new Date(myDate)
this should convert myDate to timeStamp

Generate an RFC 3339 timestamp similar to Google Tasks API?

I am in the process of building an app that syncs with Google Tasks. As part part of the syncing, I want to compare the local task and the API task, and see which one has been changed more recently.
Each task from Google's API contains an updated property, which looks like this:
2011-08-30T13:22:53.108Z
Now I would like to generate a timestamp similar to that, so that every time I update a task on my app it sets a new updated value. To generate the RFC 3339 timestamp I am using - http://cbas.pandion.im/2009/10/generating-rfc-3339-timestamps-in.html which generates something like this:
2011-08-30T09:30:16.768-04:00
The issue is, the API date is always coming back as "greater" than the local date, even when the local date is newer. I'm guessing it has something to do with the different formatting between the two.
Here are two dates, the top is from the Google Tasks API (from about 10 minutes ago), and the bottom one was generated locally a minute ago. When compared which is greater, it's telling me the top one is.
2011-08-30T13:22:53.108Z
2011-08-30T09:41:00.735-04:00
Is my formatting wrong? What I am doing wrong here? Any help on this is really appreciated.

It seems like a lot of complicated answers have been given, but this works just fine, does it not?
new Date().toISOString()

The formatting is ISO so new Date().toISOString() will give you that form. Which as I'm reading might need to be shimmed:
/* use a function for the exact format desired... */
function ISODateString(d){
function pad(n){return n<10 ? '0'+n : n}
return d.getUTCFullYear()+'-'
+ pad(d.getUTCMonth()+1)+'-'
+ pad(d.getUTCDate())+'T'
+ pad(d.getUTCHours())+':'
+ pad(d.getUTCMinutes())+':'
+ pad(d.getUTCSeconds())+'Z'}
var d = new Date();
print(ISODateString(d)); // prints something like 2009-09-28T19:03:12Z
Source: https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Date

I've found the moment.js library nice for working with time in javascript. moment().format() yields a timestamp in the format expected by the Google API for a datetime. Or, to not depend on the default format being correct for your application,
moment().format("YYYY-MM-DDTHH:mm:ssZ")
All the string options (including fractional seconds if that's what you need): http://momentjs.com/docs/#/displaying/format/

If you are using Google Script, another option is to use Utilities.formatDate URL below:
https://developers.google.com/apps-script/reference/utilities/utilities#formatDate(Date,String,String)
Sample code from above URL:
// This formats the date as Greenwich Mean Time in the format
// year-month-dateThour-minute-second.
var formattedDate = Utilities.formatDate(new Date(), "GMT", "yyyy-MM-dd'T'HH:mm:ss'Z'");

Using date-fns, this is very elegant:
import { formatRFC3339 } from 'date-fns'
const result = formatRFC3339(new Date(2019, 8, 18, 19, 0, 52))
//=> '2019-09-18T19:00:52Z'
Source:

try this:
Date.prototype.setRFC3339 = function(dString) {
var utcOffset, offsetSplitChar;
var offsetMultiplier = 1;
var dateTime = dString.split("T");
var date = dateTime[0].split("-");
var time = dateTime[1].split(":");
var offsetField = time[time.length - 1];
var offsetString;
offsetFieldIdentifier = offsetField.charAt(offsetField.length - 1);
if (offsetFieldIdentifier == "Z") {
utcOffset = 0;
time[time.length - 1] = offsetField.substr(0, offsetField.length - 2);
} else {
if (offsetField[offsetField.length - 1].indexOf("+") != -1) {
offsetSplitChar = "+";
offsetMultiplier = 1;
} else {
offsetSplitChar = "-";
offsetMultiplier = -1;
}
offsetString = offsetField.split(offsetSplitChar);
time[time.length - 1] == offsetString[0];
offsetString = offsetString[1].split(":");
utcOffset = (offsetString[0] * 60) + offsetString[1];
utcOffset = utcOffset * 60 * 1000;
}
this.setTime(Date.UTC(date[0], date[1] - 1, date[2], time[0], time[1], time[2]) + (utcOffset * offsetMultiplier));
return this;
};
source: http://blog.toppingdesign.com/2009/08/13/fast-rfc-3339-date-processing-in-javascript/

The Z behind the first date indicates it's UTC (Zulu) time, without the Z it will use the local (computer) time, which could be several time zones off.
See: http://en.wikipedia.org/wiki/UTC

It looks more pretty:
new Date().toISOString().split('.')[0] + 'Z'

Comparing date part only without comparing time in JavaScript

What is wrong with the code below?
Maybe it would be simpler to just compare date and not time. I am not sure how to do this either, and I searched, but I couldn't find my exact problem.
BTW, when I display the two dates in an alert, they show as exactly the same.
My code:
window.addEvent('domready', function() {
var now = new Date();
var input = $('datum').getValue();
var dateArray = input.split('/');
var userMonth = parseInt(dateArray[1])-1;
var userDate = new Date();
userDate.setFullYear(dateArray[2], userMonth, dateArray[0], now.getHours(), now.getMinutes(), now.getSeconds(), now.getMilliseconds());
if (userDate > now)
{
alert(now + '\n' + userDate);
}
});
Is there a simpler way to compare dates and not including the time?

I'm still learning JavaScript, and the only way that I've found which works for me to compare two dates without the time is to use the setHours method of the Date object and set the hours, minutes, seconds and milliseconds to zero. Then compare the two dates.
For example,
date1 = new Date()
date2 = new Date(2011,8,20)
date2 will be set with hours, minutes, seconds and milliseconds to zero, but date1 will have them set to the time that date1 was created. To get rid of the hours, minutes, seconds and milliseconds on date1 do the following:
date1.setHours(0,0,0,0)
Now you can compare the two dates as DATES only without worrying about time elements.

BEWARE THE TIMEZONE
Using the date object to represent just-a-date straight away gets you into a huge excess precision problem. You need to manage time and timezone to keep them out, and they can sneak back in at any step. The accepted answer to this question falls into the trap.
A javascript date has no notion of timezone. It's a moment in time (ticks since the epoch) with handy (static) functions for translating to and from strings, using by default the "local" timezone of the device, or, if specified, UTC or another timezone. To represent just-a-date™ with a date object, you want your dates to represent UTC midnight at the start of the date in question. This is a common and necessary convention that lets you work with dates regardless of the season or timezone of their creation. So you need to be very vigilant to manage the notion of timezone, both when you create your midnight UTC Date object, and when you serialize it.
Lots of folks are confused by the default behaviour of the console. If you spray a date to the console, the output you see will include your timezone. This is just because the console calls toString() on your date, and toString() gives you a local represenation. The underlying date has no timezone! (So long as the time matches the timezone offset, you still have a midnight UTC date object)
Deserializing (or creating midnight UTC Date objects)
This is the rounding step, with the trick that there are two "right" answers. Most of the time, you will want your date to reflect the local timezone of the user. What's the date here where I am.. Users in NZ and US can click at the same time and usually get different dates. In that case, do this...
// create a date (utc midnight) reflecting the value of myDate and the environment's timezone offset.
new Date(Date.UTC(myDate.getFullYear(),myDate.getMonth(), myDate.getDate()));
Sometimes, international comparability trumps local accuracy. In that case, do this...
// the date in London of a moment in time. Device timezone is ignored.
new Date(Date.UTC(myDate.getUTCFullYear(), myDate.getUTCMonth(), myDate.getUTCDate()));
Deserialize a date
Often dates on the wire will be in the format YYYY-MM-DD. To deserialize them, do this...
var midnightUTCDate = new Date( dateString + 'T00:00:00Z');
Serializing
Having taken care to manage timezone when you create, you now need to be sure to keep timezone out when you convert back to a string representation. So you can safely use...
toISOString()
getUTCxxx()
getTime() //returns a number with no time or timezone.
.toLocaleDateString("fr",{timeZone:"UTC"}) // whatever locale you want, but ALWAYS UTC.
And totally avoid everything else, especially...
getYear(),getMonth(),getDate()
So to answer your question, 7 years too late...
<input type="date" onchange="isInPast(event)">
<script>
var isInPast = function(event){
var userEntered = new Date(event.target.valueAsNumber); // valueAsNumber has no time or timezone!
var now = new Date();
var today = new Date(Date.UTC(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate() ));
if(userEntered.getTime() < today.getTime())
alert("date is past");
else if(userEntered.getTime() == today.getTime())
alert("date is today");
else
alert("date is future");
}
</script>
See it running...
Update 2022... free stuff with tests ...
The code below is now an npm package, Epoq. The code is on github. You're welcome :-)
Update 2019... free stuff...
Given the popularity of this answer, I've put it all in code. The following function returns a wrapped date object, and only exposes those functions that are safe to use with just-a-date™.
Call it with a Date object and it will resolve to JustADate reflecting the timezone of the user. Call it with a string: if the string is an ISO 8601 with timezone specified, we'll just round off the time part. If timezone is not specified, we'll convert it to a date reflecting the local timezone, just as for date objects.
function JustADate(initDate){
var utcMidnightDateObj = null
// if no date supplied, use Now.
if(!initDate)
initDate = new Date();
// if initDate specifies a timezone offset, or is already UTC, just keep the date part, reflecting the date _in that timezone_
if(typeof initDate === "string" && initDate.match(/(-\d\d|(\+|-)\d{2}:\d{2}|Z)$/gm)){
utcMidnightDateObj = new Date( initDate.substring(0,10) + 'T00:00:00Z');
} else {
// if init date is not already a date object, feed it to the date constructor.
if(!(initDate instanceof Date))
initDate = new Date(initDate);
// Vital Step! Strip time part. Create UTC midnight dateObj according to local timezone.
utcMidnightDateObj = new Date(Date.UTC(initDate.getFullYear(),initDate.getMonth(), initDate.getDate()));
}
return {
toISOString:()=>utcMidnightDateObj.toISOString(),
getUTCDate:()=>utcMidnightDateObj.getUTCDate(),
getUTCDay:()=>utcMidnightDateObj.getUTCDay(),
getUTCFullYear:()=>utcMidnightDateObj.getUTCFullYear(),
getUTCMonth:()=>utcMidnightDateObj.getUTCMonth(),
setUTCDate:(arg)=>utcMidnightDateObj.setUTCDate(arg),
setUTCFullYear:(arg)=>utcMidnightDateObj.setUTCFullYear(arg),
setUTCMonth:(arg)=>utcMidnightDateObj.setUTCMonth(arg),
addDays:(days)=>{
utcMidnightDateObj.setUTCDate(utcMidnightDateObj.getUTCDate + days)
},
toString:()=>utcMidnightDateObj.toString(),
toLocaleDateString:(locale,options)=>{
options = options || {};
options.timeZone = "UTC";
locale = locale || "en-EN";
return utcMidnightDateObj.toLocaleDateString(locale,options)
}
}
}
// if initDate already has a timezone, we'll just use the date part directly
console.log(JustADate('1963-11-22T12:30:00-06:00').toLocaleDateString())
// Test case from #prototype's comment
console.log("#prototype's issue fixed... " + JustADate('1963-11-22').toLocaleDateString())

How about this?
Date.prototype.withoutTime = function () {
var d = new Date(this);
d.setHours(0, 0, 0, 0);
return d;
}
It allows you to compare the date part of the date like this without affecting the value of your variable:
var date1 = new Date(2014,1,1);
new Date().withoutTime() > date1.withoutTime(); // true

Using Moment.js
If you have the option of including a third-party library, it's definitely worth taking a look at Moment.js. It makes working with Date and DateTime much, much easier.
For example, seeing if one Date comes after another Date but excluding their times, you would do something like this:
var date1 = new Date(2016,9,20,12,0,0); // October 20, 2016 12:00:00
var date2 = new Date(2016,9,20,12,1,0); // October 20, 2016 12:01:00
// Comparison including time.
moment(date2).isAfter(date1); // => true
// Comparison excluding time.
moment(date2).isAfter(date1, 'day'); // => false
The second parameter you pass into isAfter is the precision to do the comparison and can be any of year, month, week, day, hour, minute or second.

Simply compare using .toDateString like below:
new Date().toDateString();
This will return you date part only and not time or timezone, like this:
"Fri Feb 03 2017"
Hence both date can be compared in this format likewise without time part of it.

Just use toDateString() on both dates. toDateString doesn't include the time, so for 2 times on the same date, the values will be equal, as demonstrated below.
var d1 = new Date(2019,01,01,1,20)
var d2 = new Date(2019,01,01,2,20)
console.log(d1==d2) // false
console.log(d1.toDateString() == d2.toDateString()) // true
Obviously some of the timezone concerns expressed elsewhere on this question are valid, but in many scenarios, those are not relevant.

If you are truly comparing date only with no time component, another solution that may feel wrong but works and avoids all Date() time and timezone headaches is to compare the ISO string date directly using string comparison:
> "2019-04-22" <= "2019-04-23"
true
> "2019-04-22" <= "2019-04-22"
true
> "2019-04-22" <= "2019-04-21"
false
> "2019-04-22" === "2019-04-22"
true
You can get the current date (UTC date, not neccesarily the user's local date) using:
> new Date().toISOString().split("T")[0]
"2019-04-22"
My argument in favor of it is programmer simplicity -- you're much less likely to botch this than trying to handle datetimes and offsets correctly, probably at the cost of speed (I haven't compared performance)

This might be a little cleaner version, also note that you should always use a radix when using parseInt.
window.addEvent('domready', function() {
// Create a Date object set to midnight on today's date
var today = new Date((new Date()).setHours(0, 0, 0, 0)),
input = $('datum').getValue(),
dateArray = input.split('/'),
// Always specify a radix with parseInt(), setting the radix to 10 ensures that
// the number is interpreted as a decimal. It is particularly important with
// dates, if the user had entered '09' for the month and you don't use a
// radix '09' is interpreted as an octal number and parseInt would return 0, not 9!
userMonth = parseInt(dateArray[1], 10) - 1,
// Create a Date object set to midnight on the day the user specified
userDate = new Date(dateArray[2], userMonth, dateArray[0], 0, 0, 0, 0);
// Convert date objects to milliseconds and compare
if(userDate.getTime() > today.getTime())
{
alert(today+'\n'+userDate);
}
});
Checkout the MDC parseInt page for more information about the radix.
JSLint is a great tool for catching things like a missing radix and many other things that can cause obscure and hard to debug errors. It forces you to use better coding standards so you avoid future headaches. I use it on every JavaScript project I code.

An efficient and correct way to compare dates is:
Math.floor(date1.getTime() / 86400000) > Math.floor(date2.getTime() / 86400000);
It ignores the time part, it works for different timezones, and you can compare for equality == too. 86400000 is the number of milliseconds in a day (= 24*60*60*1000).
Beware that the equality operator == should never be used for comparing Date objects because it fails when you would expect an equality test to work because it is comparing two Date objects (and does not compare the two dates) e.g.:
> date1;
outputs: Thu Mar 08 2018 00:00:00 GMT+1300
> date2;
outputs: Thu Mar 08 2018 00:00:00 GMT+1300
> date1 == date2;
outputs: false
> Math.floor(date1.getTime() / 86400000) == Math.floor(date2.getTime() / 86400000);
outputs: true
Notes: If you are comparing Date objects that have the time part set to zero, then you could use date1.getTime() == date2.getTime() but it is hardly worth the optimisation. You can use <, >, <=, or >= when comparing Date objects directly because these operators first convert the Date object by calling .valueOf() before the operator does the comparison.

As I don't see here similar approach, and I'm not enjoying setting h/m/s/ms to 0, as it can cause problems with accurate transition to local time zone with changed date object (I presume so), let me introduce here this, written few moments ago, lil function:
+: Easy to use, makes a basic comparison operations done (comparing day, month and year without time.)
-: It seems that this is a complete opposite of "out of the box" thinking.
function datecompare(date1, sign, date2) {
var day1 = date1.getDate();
var mon1 = date1.getMonth();
var year1 = date1.getFullYear();
var day2 = date2.getDate();
var mon2 = date2.getMonth();
var year2 = date2.getFullYear();
if (sign === '===') {
if (day1 === day2 && mon1 === mon2 && year1 === year2) return true;
else return false;
}
else if (sign === '>') {
if (year1 > year2) return true;
else if (year1 === year2 && mon1 > mon2) return true;
else if (year1 === year2 && mon1 === mon2 && day1 > day2) return true;
else return false;
}
}
Usage:
datecompare(date1, '===', date2) for equality check,
datecompare(date1, '>', date2) for greater check,
!datecompare(date1, '>', date2) for less or equal check
Also, obviously, you can switch date1 and date2 in places to achieve any other simple comparison.

This JS will change the content after the set date
here's the same thing but on w3schools
date1 = new Date()
date2 = new Date(2019,5,2) //the date you are comparing
date1.setHours(0,0,0,0)
var stockcnt = document.getElementById('demo').innerHTML;
if (date1 > date2){
document.getElementById('demo').innerHTML="yes"; //change if date is > set date (date2)
}else{
document.getElementById('demo').innerHTML="hello"; //change if date is < set date (date2)
}
<p id="demo">hello</p> <!--What will be changed-->
<!--if you check back in tomorrow, it will say yes instead of hello... or you could change the date... or change > to <-->

The date.js library is handy for these things. It makes all JS date-related scriping a lot easier.

This is the way I do it:
var myDate = new Date($('input[name=frequency_start]').val()).setHours(0,0,0,0);
var today = new Date().setHours(0,0,0,0);
if(today>myDate){
jAlert('Please Enter a date in the future','Date Start Error', function(){
$('input[name=frequency_start]').focus().select();
});
}

After reading this question quite same time after it is posted I have decided to post another solution, as I didn't find it that quite satisfactory, at least to my needs:
I have used something like this:
var currentDate= new Date().setHours(0,0,0,0);
var startDay = new Date(currentDate - 86400000 * 2);
var finalDay = new Date(currentDate + 86400000 * 2);
In that way I could have used the dates in the format I wanted for processing afterwards. But this was only for my need, but I have decided to post it anyway, maybe it will help someone

This works for me:
export default (chosenDate) => {
const now = new Date();
const today = new Date(Date.UTC(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate()));
const splitChosenDate = chosenDate.split('/');
today.setHours(0, 0, 0, 0);
const fromDate = today.getTime();
const toDate = new Date(splitChosenDate[2], splitChosenDate[1] - 1, splitChosenDate[0]).getTime();
return toDate < fromDate;
};
In accepted answer, there is timezone issue and in the other time is not 00:00:00

Make sure you construct userDate with a 4 digit year as setFullYear(10, ...) !== setFullYear(2010, ...).

You can use some arithmetic with the total of ms.
var date = new Date(date1);
date.setHours(0, 0, 0, 0);
var diff = date2.getTime() - date.getTime();
return diff >= 0 && diff < 86400000;
I like this because no updates to the original dates are made and perfom faster than string split and compare.
Hope this help!

Comparing with setHours() will be a solution. Sample:
var d1 = new Date();
var d2 = new Date("2019-2-23");
if(d1.setHours(0,0,0,0) == d2.setHours(0,0,0,0)){
console.log(true)
}else{
console.log(false)
}

I know this question have been already answered and this may not be the best way, but in my scenario its working perfectly, so I thought it may help someone like me.
if you have date string as
String dateString="2018-01-01T18:19:12.543";
and you just want to compare the date part with another Date object in JS,
var anotherDate=new Date(); //some date
then you have to convert the string to Date object by using new Date("2018-01-01T18:19:12.543");
and here is the trick :-
var valueDate =new Date(new Date(dateString).toDateString());
return valueDate.valueOf() == anotherDate.valueOf(); //here is the final result
I have used toDateString() of Date object of JS, which returns the Date string only.
Note: Don't forget to use the .valueOf() function while comparing the dates.
more info about .valeOf() is here reference
Happy codding.

This will help. I managed to get it like this.
var currentDate = new Date(new Date().getFullYear(), new Date().getMonth() , new Date().getDate())

var fromdate = new Date(MM/DD/YYYY);
var todate = new Date(MM/DD/YYYY);
if (fromdate > todate){
console.log('False');
}else{
console.log('True');
}
if your date formate is different then use moment.js library to convert the format of your date and then use above code for compare two date
Example :
If your Date is in "DD/MM/YYYY" and wants to convert it into "MM/DD/YYYY" then see the below code example
var newfromdate = new Date(moment(fromdate, "DD/MM/YYYY").format("MM/DD/YYYY"));
console.log(newfromdate);
var newtodate = new Date(moment(todate, "DD/MM/YYYY").format("MM/DD/YYYY"));
console.log(newtodate);

You can use fp_incr(0). Which sets the timezone part to midnight and returns a date object.

Compare Date and Time:
var t1 = new Date(); // say, in ISO String = '2022-01-21T12:30:15.422Z'
var t2 = new Date(); // say, in ISO String = '2022-01-21T12:30:15.328Z'
var t3 = t1;
Compare 2 date objects by milliseconds level:
console.log(t1 === t2); // false - Bcos there is some milliseconds difference
console.log(t1 === t3); // true - Both dates have milliseconds level same values
Compare 2 date objects ONLY by date (Ignore any time difference):
console.log(t1.toISOString().split('T')[0] === t2.toISOString().split('T')[0]);
// true; '2022-01-21' === '2022-01-21'
Compare 2 date objects ONLY by time(ms) (Ignore any date difference):
console.log(t1.toISOString().split('T')[1] === t3.toISOString().split('T')[1]);
// true; '12:30:15.422Z' === '12:30:15.422Z'
Above 2 methods uses toISOString() method so you no need to worry about the time zone difference across the countries.

One option that I ended up using was to use the diff function of Moment.js. By calling something like start.diff(end, 'days') you can compare difference in whole numbers of days.

Works for me:
I needed to compare a date to a local dateRange
let dateToCompare = new Date().toLocaleDateString().split("T")[0])
let compareTime = new Date(dateToCompare).getTime()
let startDate = new Date().toLocaleDateString().split("T")[0])
let startTime = new Date(startDate).getTime()
let endDate = new Date().toLocaleDateString().split("T")[0])
let endTime = new Date(endDate).getTime()
return compareTime >= startTime && compareTime <= endTime

As per usual. Too little, too late.
Nowadays use of momentjs is discouraged (their words, not mine) and dayjs is preferred.
One can use dayjs's isSame.
https://day.js.org/docs/en/query/is-same
dayjs().isSame('2011-01-01', 'date')
There are also a bunch of other units you can use for the comparisons:
https://day.js.org/docs/en/manipulate/start-of#list-of-all-available-units

Using javascript you can set time values to zero for existing date objects and then parse back to Date. After parsing back to Date, Time value is 0 for both and you can do further comparison
let firstDate = new Date(mydate1.setHours(0, 0, 0, 0));
let secondDate = new Date(mydate2.setHours(0, 0, 0, 0));
if (selectedDate == currentDate)
{
console.log('same date');
}
else
{
console.log(`not same date`);
}

Use a library that knows what it's doing
https://day.js.org/docs/en/query/is-same-or-before
dayjs().isSameOrBefore(date, 'day')