I have a Date object. How do I render the title portion of the following snippet?
<abbr title="2010-04-02T14:12:07">A couple days ago</abbr>
I have the "relative time in words" portion from another library.
I've tried the following:
function isoDate(msSinceEpoch) {
var d = new Date(msSinceEpoch);
return d.getUTCFullYear() + '-' + (d.getUTCMonth() + 1) + '-' + d.getUTCDate() + 'T' +
d.getUTCHours() + ':' + d.getUTCMinutes() + ':' + d.getUTCSeconds();
}
But that gives me:
"2010-4-2T3:19"
There is already a function called toISOString():
var date = new Date();
date.toISOString(); //"2011-12-19T15:28:46.493Z"
If, somehow, you're on a browser that doesn't support it, I've got you covered:
if (!Date.prototype.toISOString) {
(function() {
function pad(number) {
var r = String(number);
if (r.length === 1) {
r = '0' + r;
}
return r;
}
Date.prototype.toISOString = function() {
return this.getUTCFullYear() +
'-' + pad(this.getUTCMonth() + 1) +
'-' + pad(this.getUTCDate()) +
'T' + pad(this.getUTCHours()) +
':' + pad(this.getUTCMinutes()) +
':' + pad(this.getUTCSeconds()) +
'.' + String((this.getUTCMilliseconds() / 1000).toFixed(3)).slice(2, 5) +
'Z';
};
}());
}
console.log(new Date().toISOString())
Note: This answer is still getting upvotes as of 2022-03. The moment.js library is deprecated. These are the two main alternatives: Luxon and Day.js, others are mentioned in the deprecation link.
Luxon
Luxon can be thought of as the evolution of Moment. It is authored by
Isaac Cambron, a long-time contributor to Moment. Please read Why does
Luxon exist? and the For Moment users pages in the Luxon
documentation.
Locales: Intl provided Time Zones: Intl provided
Day.js
Day.js is designed to be a minimalist replacement for Moment.js, using
a similar API. It is not a drop-in replacement, but if you are used to
using Moment's API and want to get moving quickly, consider using
Day.js.
Locales: Custom data files that can be individually imported Time
Zones: Intl provided, via a plugin
I use Day.js because of the size difference, but Luxon is easier to deal with.
Almost every to-ISO method on the web drops the timezone information by applying a convert to "Z"ulu time (UTC) before outputting the string. Browser's native .toISOString() also drops timezone information.
This discards valuable information, as the server, or recipient, can always convert a full ISO date to Zulu time or whichever timezone it requires, while still getting the timezone information of the sender.
The best solution I've come across is to use the Moment.js javascript library and use the following code:
To get the current ISO time with timezone information and milliseconds
now = moment().format("YYYY-MM-DDTHH:mm:ss.SSSZZ")
// "2013-03-08T20:11:11.234+0100"
now = moment().utc().format("YYYY-MM-DDTHH:mm:ss.SSSZZ")
// "2013-03-08T19:11:11.234+0000"
now = moment().utc().format("YYYY-MM-DDTHH:mm:ss") + "Z"
// "2013-03-08T19:11:11Z" <- better use the native .toISOString()
To get the ISO time of a native JavaScript Date object with timezone information but without milliseconds
var current_time = Date.now();
moment(current_time).format("YYYY-MM-DDTHH:mm:ssZZ")
This can be combined with Date.js to get functions like Date.today() whose result can then be passed to moment.
A date string formatted like this is JSON compilant, and lends itself well to get stored into a database. Python and C# seem to like it.
See the last example on page https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference:Global_Objects:Date:
/* 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();
console.log(ISODateString(d)); // Prints something like 2009-09-28T19:03:12Z
The question asked was ISO format with reduced precision. Voila:
new Date().toISOString().slice(0, 19) + 'Z'
// '2014-10-23T13:18:06Z'
Assuming the trailing Z is wanted, otherwise just omit.
Shortest, but not supported by Internet Explorer 8 and earlier:
new Date().toJSON()
If you don't need to support IE7, the following is a great, concise hack:
console.log(
JSON.parse(JSON.stringify(new Date()))
)
I typically don't want to display a UTC date since customers don't like doing the conversion in their head. To display a local ISO date, I use the function:
function toLocalIsoString(date, includeSeconds) {
function pad(n) { return n < 10 ? '0' + n : n }
var localIsoString = date.getFullYear() + '-'
+ pad(date.getMonth() + 1) + '-'
+ pad(date.getDate()) + 'T'
+ pad(date.getHours()) + ':'
+ pad(date.getMinutes()) + ':'
+ pad(date.getSeconds());
if(date.getTimezoneOffset() == 0) localIsoString += 'Z';
return localIsoString;
};
The function above omits time zone offset information (except if local time happens to be UTC), so I use the function below to show the local offset in a single location. You can also append its output to results from the above function if you wish to show the offset in each and every time:
function getOffsetFromUTC() {
var offset = new Date().getTimezoneOffset();
return ((offset < 0 ? '+' : '-')
+ pad(Math.abs(offset / 60), 2)
+ ':'
+ pad(Math.abs(offset % 60), 2))
};
toLocalIsoString uses pad. If needed, it works like nearly any pad function, but for the sake of completeness this is what I use:
// Pad a number to length using padChar
function pad(number, length, padChar) {
if (typeof length === 'undefined') length = 2;
if (typeof padChar === 'undefined') padChar = '0';
var str = "" + number;
while (str.length < length) {
str = padChar + str;
}
return str;
}
The problem with toISOString is that it gives datetime only as "Z".
ISO-8601 also defines datetime with timezone difference in hours and minutes, in the forms like 2016-07-16T19:20:30+5:30 (when timezone is ahead UTC) and 2016-07-16T19:20:30-01:00 (when timezone is behind UTC).
I don't think it is a good idea to use another plugin, moment.js for such a small task, especially when you can get it with a few lines of code.
Once you have the timezone offset in hours and minutes, you can append to a datetime string.
I wrote a blog post on it : http://usefulangle.com/post/30/javascript-get-date-time-with-offset-hours-minutes
var timezone_offset_min = new Date().getTimezoneOffset(),
offset_hrs = parseInt(Math.abs(timezone_offset_min / 60)),
offset_min = Math.abs(timezone_offset_min % 60),
timezone_standard;
if (offset_hrs < 10)
offset_hrs = '0' + offset_hrs;
if (offset_min > 10)
offset_min = '0' + offset_min;
// getTimezoneOffset returns an offset which is positive if the local timezone is behind UTC and vice-versa.
// So add an opposite sign to the offset
// If offset is 0, it means timezone is UTC
if (timezone_offset_min < 0)
timezone_standard = '+' + offset_hrs + ':' + offset_min;
else if (timezone_offset_min > 0)
timezone_standard = '-' + offset_hrs + ':' + offset_min;
else if (timezone_offset_min == 0)
timezone_standard = 'Z';
// Timezone difference in hours and minutes
// String such as +5:30 or -6:00 or Z
console.log(timezone_standard);
There is a '+' missing after the 'T'
isoDate: function(msSinceEpoch) {
var d = new Date(msSinceEpoch);
return d.getUTCFullYear() + '-' + (d.getUTCMonth() + 1) + '-' + d.getUTCDate() + 'T'
+ d.getUTCHours() + ':' + d.getUTCMinutes() + ':' + d.getUTCSeconds();
}
should do it.
For the leading zeros you could use this from here:
function PadDigits(n, totalDigits)
{
n = n.toString();
var pd = '';
if (totalDigits > n.length)
{
for (i=0; i < (totalDigits-n.length); i++)
{
pd += '0';
}
}
return pd + n.toString();
}
Using it like this:
PadDigits(d.getUTCHours(),2)
function timeStr(d) {
return ''+
d.getFullYear()+
('0'+(d.getMonth()+1)).slice(-2)+
('0'+d.getDate()).slice(-2)+
('0'+d.getHours()).slice(-2)+
('0'+d.getMinutes()).slice(-2)+
('0'+d.getSeconds()).slice(-2);
}
I was able to get below output with very less code.
var ps = new Date('2010-04-02T14:12:07') ;
ps = ps.toDateString() + " " + ps.getHours() + ":"+ ps.getMinutes() + " hrs";
Output:
Fri Apr 02 2010 19:42 hrs
I think I have found an even better solution:
According to the wiki page Canada uses ISO 8601 as the official date format, therefore we can safely use this.
console.log(new Date("2022-12-19 00:43:00 GMT+0100").toISOString().split("T")[0]);
// results in '2022-12-18'
console.log(new Date("2022-12-19 00:43:00 GMT+0100").toLocaleDateString("en-CA"));
// results in '2022-12-19'
I would just use this small extension to Date - http://blog.stevenlevithan.com/archives/date-time-format
var date = new Date(msSinceEpoch);
date.format("isoDateTime"); // 2007-06-09T17:46:21
function getdatetime() {
d = new Date();
return (1e3-~d.getUTCMonth()*10+d.toUTCString()+1e3+d/1)
.replace(/1(..)..*?(\d+)\D+(\d+).(\S+).*(...)/,'$3-$1-$2T$4.$5Z')
.replace(/-(\d)T/,'-0$1T');
}
I found the basics on Stack Overflow somewhere (I believe it was part of some other Stack Exchange code golfing), and I improved it so it works on Internet Explorer 10 or earlier as well. It's ugly, but it gets the job done.
A short one:
console.log(new Date().toISOString().slice(0,19).replace('T', ' '))
To extend Sean's great and concise answer with some sugar and modern syntax:
// date.js
const getMonthName = (num) => {
const months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Oct', 'Nov', 'Dec'];
return months[num];
};
const formatDate = (d) => {
const date = new Date(d);
const year = date.getFullYear();
const month = getMonthName(date.getMonth());
const day = ('0' + date.getDate()).slice(-2);
const hour = ('0' + date.getHours()).slice(-2);
const minutes = ('0' + date.getMinutes()).slice(-2);
return `${year} ${month} ${day}, ${hour}:${minutes}`;
};
module.exports = formatDate;
Then eg.
import formatDate = require('./date');
const myDate = "2018-07-24T13:44:46.493Z"; // Actual value from wherever, eg. MongoDB date
console.log(formatDate(myDate)); // 2018 Jul 24, 13:44
Related
Goal: Find the local time and UTC time offset then construct the URL in following format.
Example URL: /Actions/Sleep?duration=2002-10-10T12:00:00−05:00
The format is based on the W3C recommendation. The documentation says:
For example, 2002-10-10T12:00:00−05:00 (noon on 10 October 2002,
Central Daylight Savings Time as well as Eastern Standard Time in the U.S.)
is equal to 2002-10-10T17:00:00Z, five hours later than 2002-10-10T12:00:00Z.
So based on my understanding, I need to find my local time by new Date() then use getTimezoneOffset() function to compute the difference then attach it to the end of string.
Get local time with format
var local = new Date().format("yyyy-MM-ddThh:mm:ss"); // 2013-07-02T09:00:00
Get UTC time offset by hour
var offset = local.getTimezoneOffset() / 60; // 7
Construct URL (time part only)
var duration = local + "-" + offset + ":00"; // 2013-07-02T09:00:00-7:00
The above output means my local time is 2013/07/02 9am and difference from UTC is 7 hours (UTC is 7 hours ahead of local time)
So far it seems to work but what if getTimezoneOffset() returns negative value like -120?
I'm wondering how the format should look like in such case because I cannot figure out from W3C documentation.
Here's a simple helper function that will format JS dates for you.
function toIsoString(date) {
var tzo = -date.getTimezoneOffset(),
dif = tzo >= 0 ? '+' : '-',
pad = function(num) {
return (num < 10 ? '0' : '') + num;
};
return date.getFullYear() +
'-' + pad(date.getMonth() + 1) +
'-' + pad(date.getDate()) +
'T' + pad(date.getHours()) +
':' + pad(date.getMinutes()) +
':' + pad(date.getSeconds()) +
dif + pad(Math.floor(Math.abs(tzo) / 60)) +
':' + pad(Math.abs(tzo) % 60);
}
var dt = new Date();
console.log(toIsoString(dt));
getTimezoneOffset() returns the opposite sign of the format required by the spec that you referenced.
This format is also known as ISO8601, or more precisely as RFC3339.
In this format, UTC is represented with a Z while all other formats are represented by an offset from UTC. The meaning is the same as JavaScript's, but the order of subtraction is inverted, so the result carries the opposite sign.
Also, there is no method on the native Date object called format, so your function in #1 will fail unless you are using a library to achieve this. Refer to this documentation.
If you are seeking a library that can work with this format directly, I recommend trying moment.js. In fact, this is the default format, so you can simply do this:
var m = moment(); // get "now" as a moment
var s = m.format(); // the ISO format is the default so no parameters are needed
// sample output: 2013-07-01T17:55:13-07:00
This is a well-tested, cross-browser solution, and has many other useful features.
I think it is worth considering that you can get the requested info with just a single API call to the standard library...
new Date().toLocaleString( 'sv', { timeZoneName: 'short' } );
// produces "2019-10-30 15:33:47 GMT−4"
You would have to do text swapping if you want to add the 'T' delimiter, remove the 'GMT-', or append the ':00' to the end.
But then you can easily play with the other options if you want to eg. use 12h time or omit the seconds etc.
Note that I'm using Sweden as locale because it is one of the countries that uses ISO 8601 format. I think most of the ISO countries use this 'GMT-4' format for the timezone offset other then Canada which uses the time zone abbreviation eg. "EDT" for eastern-daylight-time.
You can get the same thing from the newer standard i18n function "Intl.DateTimeFormat()"
but you have to tell it to include the time via the options or it will just give date.
My answer is a slight variation for those who just want today's date in the local timezone in the YYYY-MM-DD format.
Let me be clear:
My Goal: get today's date in the user's timezone but formatted as ISO8601 (YYYY-MM-DD)
Here is the code:
new Date().toLocaleDateString("sv") // "2020-02-23" //
This works because the Sweden locale uses the ISO 8601 format.
This is my function for the clients timezone, it's lite weight and simple
function getCurrentDateTimeMySql() {
var tzoffset = (new Date()).getTimezoneOffset() * 60000; //offset in milliseconds
var localISOTime = (new Date(Date.now() - tzoffset)).toISOString().slice(0, 19).replace('T', ' ');
var mySqlDT = localISOTime;
return mySqlDT;
}
Check this:
function dateToLocalISO(date) {
const off = date.getTimezoneOffset()
const absoff = Math.abs(off)
return (new Date(date.getTime() - off*60*1000).toISOString().substr(0,23) +
(off > 0 ? '-' : '+') +
Math.floor(absoff / 60).toFixed(0).padStart(2,'0') + ':' +
(absoff % 60).toString().padStart(2,'0'))
}
// Test it:
d = new Date()
dateToLocalISO(d)
// ==> '2019-06-21T16:07:22.181-03:00'
// Is similar to:
moment = require('moment')
moment(d).format('YYYY-MM-DDTHH:mm:ss.SSSZ')
// ==> '2019-06-21T16:07:22.181-03:00'
You can achieve this with a few simple extension methods. The following Date extension method returns just the timezone component in ISO format, then you can define another for the date/time part and combine them for a complete date-time-offset string.
Date.prototype.getISOTimezoneOffset = function () {
const offset = this.getTimezoneOffset();
return (offset < 0 ? "+" : "-") + Math.floor(Math.abs(offset / 60)).leftPad(2) + ":" + (Math.abs(offset % 60)).leftPad(2);
}
Date.prototype.toISOLocaleString = function () {
return this.getFullYear() + "-" + (this.getMonth() + 1).leftPad(2) + "-" +
this.getDate().leftPad(2) + "T" + this.getHours().leftPad(2) + ":" +
this.getMinutes().leftPad(2) + ":" + this.getSeconds().leftPad(2) + "." +
this.getMilliseconds().leftPad(3);
}
Number.prototype.leftPad = function (size) {
var s = String(this);
while (s.length < (size || 2)) {
s = "0" + s;
}
return s;
}
Example usage:
var date = new Date();
console.log(date.toISOLocaleString() + date.getISOTimezoneOffset());
// Prints "2020-08-05T16:15:46.525+10:00"
I know it's 2020 and most people are probably using Moment.js by now, but a simple copy & pastable solution is still sometimes handy to have.
(The reason I split the date/time and offset methods is because I'm using an old Datejs library which already provides a flexible toString method with custom format specifiers, but just doesn't include the timezone offset. Hence, I added toISOLocaleString for anyone without said library.)
Just my two cents here
I was facing this issue with datetimes so what I did is this:
const moment = require('moment-timezone')
const date = moment.tz('America/Bogota').format()
Then save date to db to be able to compare it from some query.
To install moment-timezone
npm i moment-timezone
No moment.js needed: Here's a full round trip answer, from an input type of "datetime-local" which outputs an ISOLocal string to UTCseconds at GMT and back:
<input type="datetime-local" value="2020-02-16T19:30">
isoLocal="2020-02-16T19:30"
utcSeconds=new Date(isoLocal).getTime()/1000
//here you have 1581899400 for utcSeconds
let isoLocal=new Date(utcSeconds*1000-new Date().getTimezoneOffset()*60000).toISOString().substring(0,16)
2020-02-16T19:30
date to ISO string,
with local(computer) time zone,
with or without milliseconds
ISO ref: https://en.wikipedia.org/wiki/ISO_8601
how to use: toIsoLocalTime(new Date())
function toIsoLocalTime(value) {
if (value instanceof Date === false)
value = new Date();
const off = value.getTimezoneOffset() * -1;
const del = value.getMilliseconds() ? 'Z' : '.'; // have milliseconds ?
value = new Date(value.getTime() + off * 60000); // add or subtract time zone
return value
.toISOString()
.split(del)[0]
+ (off < 0 ? '-' : '+')
+ ('0' + Math.abs(Math.floor(off / 60))).substr(-2)
+ ':'
+ ('0' + Math.abs(off % 60)).substr(-2);
}
function test(value) {
const event = new Date(value);
console.info(value + ' -> ' + toIsoLocalTime(event) + ', test = ' + (event.getTime() === (new Date(toIsoLocalTime(event))).getTime() ));
}
test('2017-06-14T10:00:00+03:00'); // test with timezone
test('2017-06-14T10:00:00'); // test with local timezone
test('2017-06-14T10:00:00Z'); // test with UTC format
test('2099-12-31T23:59:59.999Z'); // date with milliseconds
test((new Date()).toString()); // now
consider using moment (like Matt's answer).
From version 2.20.0, you may call .toISOString(true) to prevent UTC conversion:
console.log(moment().toISOString(true));
// sample output: 2022-04-06T16:26:36.758+03:00
Use Temporal.
Temporal.Now.zonedDateTimeISO().toString()
// '2022-08-09T14:16:47.762797591-07:00[America/Los_Angeles]'
To omit the fractional seconds and IANA time zone:
Temporal.Now.zonedDateTimeISO().toString({
timeZoneName: "never",
fractionalSecondDigits: 0
})
// '2022-08-09T14:18:34-07:00'
Note: Temporal is currently (2022) available as a polyfill, but will soon be available in major browsers.
With luxon:
DateTime.now().toISODate() // 2022-05-23
Here are the functions I used for this end:
function localToGMTStingTime(localTime = null) {
var date = localTime ? new Date(localTime) : new Date();
return new Date(date.getTime() + (date.getTimezoneOffset() * 60000)).toISOString();
};
function GMTToLocalStingTime(GMTTime = null) {
var date = GMTTime ? new Date(GMTTime) : new Date();;
return new Date(date.getTime() - (date.getTimezoneOffset() * 60000)).toISOString();
};
let myDate = new Date(dateToBeFormatted * 1000); // depends if you have milliseconds, or seconds, then the * 1000 might be not, or required.
timeOffset = myDate.getTimezoneOffset();
myDate = new Date(myDate.getTime() - (timeOffset * 60 * 1000));
console.log(myDate.toISOString().split('T')[0]);
Inspired by https://stackoverflow.com/a/29774197/11127383, including timezone offset comment.
a simple way to get:
//using a sample date
let iso_str = '2022-06-11T01:51:59.618Z';
let d = new Date(iso_str);
let tz = 'America/Santiago'
let options = {
timeZone:tz ,
timeZoneName:'longOffset',
year: 'numeric',
month: 'numeric',
day: 'numeric',
hour: 'numeric',
minute: 'numeric',
second: 'numeric',
fractionalSecondDigits: 3
}
str_locale = d.toLocaleString("sv-SE",options);
iso_str_tz = str_locale.replace(/(\d{4})-(\d{2})-(\d{2})\s+(\d{2}):(\d{2}):(\d{2}),(\d+)\s+/,'$1-$2-$3T$4:$5:$6.$7').replace('GMT−', '-' ).replace('GMT+','+')
console.log('iso_str : ',iso_str);
console.log('str_locale : ',str_locale);
console.log('iso_str_tz : ',iso_str_tz);
console.log('iso_str_tz --> date : ',new Date(iso_str_tz));
console.log('iso_str_tz --> iso_str: ',new Date(iso_str_tz).toISOString());
Using moment.js, you can use keepOffset parameter of toISOString:
toISOString(keepOffset?: boolean): string;
moment().toISOString(true)
Alternative approach with dayjs
import dayjs from "dayjs"
const formattedDateTime = dayjs(new Date()).format()
console.log(formattedDateTime) // Prints 2022-11-09T07:49:29+03:00
Here's another way a convert your date with an offset.
function toCustomDateString(date, offset) {
function pad(number) {
if (number < 10) {
return "0" + number;
}
return number;
}
var offsetHours = offset / 60;
var offsetMinutes = offset % 60;
var sign = (offset > 0) ? "+" : "-";
offsetHours = pad(Math.floor(Math.abs(offsetHours)));
offsetMinutes = pad(Math.abs(offsetMinutes));
return date.getFullYear() +
"-" + pad(date.getMonth() + 1) +
"-" + pad(date.getDate()) +
"T" + pad(date.getHours()) +
":" + pad(date.getMinutes()) +
":" + pad(date.getSeconds()) +
sign + offsetHours +
":" + offsetMinutes;
}
Then you can use it like this:
var date = new Date();
var offset = 330; // offset in minutes from UTC, for India it is 330 minutes ahead of UTC
var customDateString = toCustomDateString(date, offset);
console.log(customDateString);
// Output: "2023-02-09T10:29:31+05:30"
function setDate(){
var now = new Date();
now.setMinutes(now.getMinutes() - now.getTimezoneOffset());
var timeToSet = now.toISOString().slice(0,16);
/*
If you have an element called "eventDate" like the following:
<input type="datetime-local" name="eventdate" id="eventdate" />
and you would like to set the current and minimum time then use the following:
*/
var elem = document.getElementById("eventDate");
elem.value = timeToSet;
elem.min = timeToSet;
}
I found another more easy solution:
let now = new Date();
// correct time zone offset for generating iso string
now.setMinutes(now.getMinutes() - now.getTimezoneOffset())
now = now.toISOString();
I undo the timezone offset by substracting it from the current date object.
The UTC time from the date object is now pointing to the local time.
That gives you the possibility to get the iso date for the local time.
Goal: Find the local time and UTC time offset then construct the URL in following format.
Example URL: /Actions/Sleep?duration=2002-10-10T12:00:00−05:00
The format is based on the W3C recommendation. The documentation says:
For example, 2002-10-10T12:00:00−05:00 (noon on 10 October 2002,
Central Daylight Savings Time as well as Eastern Standard Time in the U.S.)
is equal to 2002-10-10T17:00:00Z, five hours later than 2002-10-10T12:00:00Z.
So based on my understanding, I need to find my local time by new Date() then use getTimezoneOffset() function to compute the difference then attach it to the end of string.
Get local time with format
var local = new Date().format("yyyy-MM-ddThh:mm:ss"); // 2013-07-02T09:00:00
Get UTC time offset by hour
var offset = local.getTimezoneOffset() / 60; // 7
Construct URL (time part only)
var duration = local + "-" + offset + ":00"; // 2013-07-02T09:00:00-7:00
The above output means my local time is 2013/07/02 9am and difference from UTC is 7 hours (UTC is 7 hours ahead of local time)
So far it seems to work but what if getTimezoneOffset() returns negative value like -120?
I'm wondering how the format should look like in such case because I cannot figure out from W3C documentation.
Here's a simple helper function that will format JS dates for you.
function toIsoString(date) {
var tzo = -date.getTimezoneOffset(),
dif = tzo >= 0 ? '+' : '-',
pad = function(num) {
return (num < 10 ? '0' : '') + num;
};
return date.getFullYear() +
'-' + pad(date.getMonth() + 1) +
'-' + pad(date.getDate()) +
'T' + pad(date.getHours()) +
':' + pad(date.getMinutes()) +
':' + pad(date.getSeconds()) +
dif + pad(Math.floor(Math.abs(tzo) / 60)) +
':' + pad(Math.abs(tzo) % 60);
}
var dt = new Date();
console.log(toIsoString(dt));
getTimezoneOffset() returns the opposite sign of the format required by the spec that you referenced.
This format is also known as ISO8601, or more precisely as RFC3339.
In this format, UTC is represented with a Z while all other formats are represented by an offset from UTC. The meaning is the same as JavaScript's, but the order of subtraction is inverted, so the result carries the opposite sign.
Also, there is no method on the native Date object called format, so your function in #1 will fail unless you are using a library to achieve this. Refer to this documentation.
If you are seeking a library that can work with this format directly, I recommend trying moment.js. In fact, this is the default format, so you can simply do this:
var m = moment(); // get "now" as a moment
var s = m.format(); // the ISO format is the default so no parameters are needed
// sample output: 2013-07-01T17:55:13-07:00
This is a well-tested, cross-browser solution, and has many other useful features.
I think it is worth considering that you can get the requested info with just a single API call to the standard library...
new Date().toLocaleString( 'sv', { timeZoneName: 'short' } );
// produces "2019-10-30 15:33:47 GMT−4"
You would have to do text swapping if you want to add the 'T' delimiter, remove the 'GMT-', or append the ':00' to the end.
But then you can easily play with the other options if you want to eg. use 12h time or omit the seconds etc.
Note that I'm using Sweden as locale because it is one of the countries that uses ISO 8601 format. I think most of the ISO countries use this 'GMT-4' format for the timezone offset other then Canada which uses the time zone abbreviation eg. "EDT" for eastern-daylight-time.
You can get the same thing from the newer standard i18n function "Intl.DateTimeFormat()"
but you have to tell it to include the time via the options or it will just give date.
My answer is a slight variation for those who just want today's date in the local timezone in the YYYY-MM-DD format.
Let me be clear:
My Goal: get today's date in the user's timezone but formatted as ISO8601 (YYYY-MM-DD)
Here is the code:
new Date().toLocaleDateString("sv") // "2020-02-23" //
This works because the Sweden locale uses the ISO 8601 format.
This is my function for the clients timezone, it's lite weight and simple
function getCurrentDateTimeMySql() {
var tzoffset = (new Date()).getTimezoneOffset() * 60000; //offset in milliseconds
var localISOTime = (new Date(Date.now() - tzoffset)).toISOString().slice(0, 19).replace('T', ' ');
var mySqlDT = localISOTime;
return mySqlDT;
}
Check this:
function dateToLocalISO(date) {
const off = date.getTimezoneOffset()
const absoff = Math.abs(off)
return (new Date(date.getTime() - off*60*1000).toISOString().substr(0,23) +
(off > 0 ? '-' : '+') +
Math.floor(absoff / 60).toFixed(0).padStart(2,'0') + ':' +
(absoff % 60).toString().padStart(2,'0'))
}
// Test it:
d = new Date()
dateToLocalISO(d)
// ==> '2019-06-21T16:07:22.181-03:00'
// Is similar to:
moment = require('moment')
moment(d).format('YYYY-MM-DDTHH:mm:ss.SSSZ')
// ==> '2019-06-21T16:07:22.181-03:00'
You can achieve this with a few simple extension methods. The following Date extension method returns just the timezone component in ISO format, then you can define another for the date/time part and combine them for a complete date-time-offset string.
Date.prototype.getISOTimezoneOffset = function () {
const offset = this.getTimezoneOffset();
return (offset < 0 ? "+" : "-") + Math.floor(Math.abs(offset / 60)).leftPad(2) + ":" + (Math.abs(offset % 60)).leftPad(2);
}
Date.prototype.toISOLocaleString = function () {
return this.getFullYear() + "-" + (this.getMonth() + 1).leftPad(2) + "-" +
this.getDate().leftPad(2) + "T" + this.getHours().leftPad(2) + ":" +
this.getMinutes().leftPad(2) + ":" + this.getSeconds().leftPad(2) + "." +
this.getMilliseconds().leftPad(3);
}
Number.prototype.leftPad = function (size) {
var s = String(this);
while (s.length < (size || 2)) {
s = "0" + s;
}
return s;
}
Example usage:
var date = new Date();
console.log(date.toISOLocaleString() + date.getISOTimezoneOffset());
// Prints "2020-08-05T16:15:46.525+10:00"
I know it's 2020 and most people are probably using Moment.js by now, but a simple copy & pastable solution is still sometimes handy to have.
(The reason I split the date/time and offset methods is because I'm using an old Datejs library which already provides a flexible toString method with custom format specifiers, but just doesn't include the timezone offset. Hence, I added toISOLocaleString for anyone without said library.)
Just my two cents here
I was facing this issue with datetimes so what I did is this:
const moment = require('moment-timezone')
const date = moment.tz('America/Bogota').format()
Then save date to db to be able to compare it from some query.
To install moment-timezone
npm i moment-timezone
No moment.js needed: Here's a full round trip answer, from an input type of "datetime-local" which outputs an ISOLocal string to UTCseconds at GMT and back:
<input type="datetime-local" value="2020-02-16T19:30">
isoLocal="2020-02-16T19:30"
utcSeconds=new Date(isoLocal).getTime()/1000
//here you have 1581899400 for utcSeconds
let isoLocal=new Date(utcSeconds*1000-new Date().getTimezoneOffset()*60000).toISOString().substring(0,16)
2020-02-16T19:30
date to ISO string,
with local(computer) time zone,
with or without milliseconds
ISO ref: https://en.wikipedia.org/wiki/ISO_8601
how to use: toIsoLocalTime(new Date())
function toIsoLocalTime(value) {
if (value instanceof Date === false)
value = new Date();
const off = value.getTimezoneOffset() * -1;
const del = value.getMilliseconds() ? 'Z' : '.'; // have milliseconds ?
value = new Date(value.getTime() + off * 60000); // add or subtract time zone
return value
.toISOString()
.split(del)[0]
+ (off < 0 ? '-' : '+')
+ ('0' + Math.abs(Math.floor(off / 60))).substr(-2)
+ ':'
+ ('0' + Math.abs(off % 60)).substr(-2);
}
function test(value) {
const event = new Date(value);
console.info(value + ' -> ' + toIsoLocalTime(event) + ', test = ' + (event.getTime() === (new Date(toIsoLocalTime(event))).getTime() ));
}
test('2017-06-14T10:00:00+03:00'); // test with timezone
test('2017-06-14T10:00:00'); // test with local timezone
test('2017-06-14T10:00:00Z'); // test with UTC format
test('2099-12-31T23:59:59.999Z'); // date with milliseconds
test((new Date()).toString()); // now
consider using moment (like Matt's answer).
From version 2.20.0, you may call .toISOString(true) to prevent UTC conversion:
console.log(moment().toISOString(true));
// sample output: 2022-04-06T16:26:36.758+03:00
Use Temporal.
Temporal.Now.zonedDateTimeISO().toString()
// '2022-08-09T14:16:47.762797591-07:00[America/Los_Angeles]'
To omit the fractional seconds and IANA time zone:
Temporal.Now.zonedDateTimeISO().toString({
timeZoneName: "never",
fractionalSecondDigits: 0
})
// '2022-08-09T14:18:34-07:00'
Note: Temporal is currently (2022) available as a polyfill, but will soon be available in major browsers.
With luxon:
DateTime.now().toISODate() // 2022-05-23
Here are the functions I used for this end:
function localToGMTStingTime(localTime = null) {
var date = localTime ? new Date(localTime) : new Date();
return new Date(date.getTime() + (date.getTimezoneOffset() * 60000)).toISOString();
};
function GMTToLocalStingTime(GMTTime = null) {
var date = GMTTime ? new Date(GMTTime) : new Date();;
return new Date(date.getTime() - (date.getTimezoneOffset() * 60000)).toISOString();
};
let myDate = new Date(dateToBeFormatted * 1000); // depends if you have milliseconds, or seconds, then the * 1000 might be not, or required.
timeOffset = myDate.getTimezoneOffset();
myDate = new Date(myDate.getTime() - (timeOffset * 60 * 1000));
console.log(myDate.toISOString().split('T')[0]);
Inspired by https://stackoverflow.com/a/29774197/11127383, including timezone offset comment.
a simple way to get:
//using a sample date
let iso_str = '2022-06-11T01:51:59.618Z';
let d = new Date(iso_str);
let tz = 'America/Santiago'
let options = {
timeZone:tz ,
timeZoneName:'longOffset',
year: 'numeric',
month: 'numeric',
day: 'numeric',
hour: 'numeric',
minute: 'numeric',
second: 'numeric',
fractionalSecondDigits: 3
}
str_locale = d.toLocaleString("sv-SE",options);
iso_str_tz = str_locale.replace(/(\d{4})-(\d{2})-(\d{2})\s+(\d{2}):(\d{2}):(\d{2}),(\d+)\s+/,'$1-$2-$3T$4:$5:$6.$7').replace('GMT−', '-' ).replace('GMT+','+')
console.log('iso_str : ',iso_str);
console.log('str_locale : ',str_locale);
console.log('iso_str_tz : ',iso_str_tz);
console.log('iso_str_tz --> date : ',new Date(iso_str_tz));
console.log('iso_str_tz --> iso_str: ',new Date(iso_str_tz).toISOString());
Using moment.js, you can use keepOffset parameter of toISOString:
toISOString(keepOffset?: boolean): string;
moment().toISOString(true)
Alternative approach with dayjs
import dayjs from "dayjs"
const formattedDateTime = dayjs(new Date()).format()
console.log(formattedDateTime) // Prints 2022-11-09T07:49:29+03:00
Here's another way a convert your date with an offset.
function toCustomDateString(date, offset) {
function pad(number) {
if (number < 10) {
return "0" + number;
}
return number;
}
var offsetHours = offset / 60;
var offsetMinutes = offset % 60;
var sign = (offset > 0) ? "+" : "-";
offsetHours = pad(Math.floor(Math.abs(offsetHours)));
offsetMinutes = pad(Math.abs(offsetMinutes));
return date.getFullYear() +
"-" + pad(date.getMonth() + 1) +
"-" + pad(date.getDate()) +
"T" + pad(date.getHours()) +
":" + pad(date.getMinutes()) +
":" + pad(date.getSeconds()) +
sign + offsetHours +
":" + offsetMinutes;
}
Then you can use it like this:
var date = new Date();
var offset = 330; // offset in minutes from UTC, for India it is 330 minutes ahead of UTC
var customDateString = toCustomDateString(date, offset);
console.log(customDateString);
// Output: "2023-02-09T10:29:31+05:30"
function setDate(){
var now = new Date();
now.setMinutes(now.getMinutes() - now.getTimezoneOffset());
var timeToSet = now.toISOString().slice(0,16);
/*
If you have an element called "eventDate" like the following:
<input type="datetime-local" name="eventdate" id="eventdate" />
and you would like to set the current and minimum time then use the following:
*/
var elem = document.getElementById("eventDate");
elem.value = timeToSet;
elem.min = timeToSet;
}
I found another more easy solution:
let now = new Date();
// correct time zone offset for generating iso string
now.setMinutes(now.getMinutes() - now.getTimezoneOffset())
now = now.toISOString();
I undo the timezone offset by substracting it from the current date object.
The UTC time from the date object is now pointing to the local time.
That gives you the possibility to get the iso date for the local time.
Goal: Find the local time and UTC time offset then construct the URL in following format.
Example URL: /Actions/Sleep?duration=2002-10-10T12:00:00−05:00
The format is based on the W3C recommendation. The documentation says:
For example, 2002-10-10T12:00:00−05:00 (noon on 10 October 2002,
Central Daylight Savings Time as well as Eastern Standard Time in the U.S.)
is equal to 2002-10-10T17:00:00Z, five hours later than 2002-10-10T12:00:00Z.
So based on my understanding, I need to find my local time by new Date() then use getTimezoneOffset() function to compute the difference then attach it to the end of string.
Get local time with format
var local = new Date().format("yyyy-MM-ddThh:mm:ss"); // 2013-07-02T09:00:00
Get UTC time offset by hour
var offset = local.getTimezoneOffset() / 60; // 7
Construct URL (time part only)
var duration = local + "-" + offset + ":00"; // 2013-07-02T09:00:00-7:00
The above output means my local time is 2013/07/02 9am and difference from UTC is 7 hours (UTC is 7 hours ahead of local time)
So far it seems to work but what if getTimezoneOffset() returns negative value like -120?
I'm wondering how the format should look like in such case because I cannot figure out from W3C documentation.
Here's a simple helper function that will format JS dates for you.
function toIsoString(date) {
var tzo = -date.getTimezoneOffset(),
dif = tzo >= 0 ? '+' : '-',
pad = function(num) {
return (num < 10 ? '0' : '') + num;
};
return date.getFullYear() +
'-' + pad(date.getMonth() + 1) +
'-' + pad(date.getDate()) +
'T' + pad(date.getHours()) +
':' + pad(date.getMinutes()) +
':' + pad(date.getSeconds()) +
dif + pad(Math.floor(Math.abs(tzo) / 60)) +
':' + pad(Math.abs(tzo) % 60);
}
var dt = new Date();
console.log(toIsoString(dt));
getTimezoneOffset() returns the opposite sign of the format required by the spec that you referenced.
This format is also known as ISO8601, or more precisely as RFC3339.
In this format, UTC is represented with a Z while all other formats are represented by an offset from UTC. The meaning is the same as JavaScript's, but the order of subtraction is inverted, so the result carries the opposite sign.
Also, there is no method on the native Date object called format, so your function in #1 will fail unless you are using a library to achieve this. Refer to this documentation.
If you are seeking a library that can work with this format directly, I recommend trying moment.js. In fact, this is the default format, so you can simply do this:
var m = moment(); // get "now" as a moment
var s = m.format(); // the ISO format is the default so no parameters are needed
// sample output: 2013-07-01T17:55:13-07:00
This is a well-tested, cross-browser solution, and has many other useful features.
I think it is worth considering that you can get the requested info with just a single API call to the standard library...
new Date().toLocaleString( 'sv', { timeZoneName: 'short' } );
// produces "2019-10-30 15:33:47 GMT−4"
You would have to do text swapping if you want to add the 'T' delimiter, remove the 'GMT-', or append the ':00' to the end.
But then you can easily play with the other options if you want to eg. use 12h time or omit the seconds etc.
Note that I'm using Sweden as locale because it is one of the countries that uses ISO 8601 format. I think most of the ISO countries use this 'GMT-4' format for the timezone offset other then Canada which uses the time zone abbreviation eg. "EDT" for eastern-daylight-time.
You can get the same thing from the newer standard i18n function "Intl.DateTimeFormat()"
but you have to tell it to include the time via the options or it will just give date.
My answer is a slight variation for those who just want today's date in the local timezone in the YYYY-MM-DD format.
Let me be clear:
My Goal: get today's date in the user's timezone but formatted as ISO8601 (YYYY-MM-DD)
Here is the code:
new Date().toLocaleDateString("sv") // "2020-02-23" //
This works because the Sweden locale uses the ISO 8601 format.
This is my function for the clients timezone, it's lite weight and simple
function getCurrentDateTimeMySql() {
var tzoffset = (new Date()).getTimezoneOffset() * 60000; //offset in milliseconds
var localISOTime = (new Date(Date.now() - tzoffset)).toISOString().slice(0, 19).replace('T', ' ');
var mySqlDT = localISOTime;
return mySqlDT;
}
Check this:
function dateToLocalISO(date) {
const off = date.getTimezoneOffset()
const absoff = Math.abs(off)
return (new Date(date.getTime() - off*60*1000).toISOString().substr(0,23) +
(off > 0 ? '-' : '+') +
Math.floor(absoff / 60).toFixed(0).padStart(2,'0') + ':' +
(absoff % 60).toString().padStart(2,'0'))
}
// Test it:
d = new Date()
dateToLocalISO(d)
// ==> '2019-06-21T16:07:22.181-03:00'
// Is similar to:
moment = require('moment')
moment(d).format('YYYY-MM-DDTHH:mm:ss.SSSZ')
// ==> '2019-06-21T16:07:22.181-03:00'
You can achieve this with a few simple extension methods. The following Date extension method returns just the timezone component in ISO format, then you can define another for the date/time part and combine them for a complete date-time-offset string.
Date.prototype.getISOTimezoneOffset = function () {
const offset = this.getTimezoneOffset();
return (offset < 0 ? "+" : "-") + Math.floor(Math.abs(offset / 60)).leftPad(2) + ":" + (Math.abs(offset % 60)).leftPad(2);
}
Date.prototype.toISOLocaleString = function () {
return this.getFullYear() + "-" + (this.getMonth() + 1).leftPad(2) + "-" +
this.getDate().leftPad(2) + "T" + this.getHours().leftPad(2) + ":" +
this.getMinutes().leftPad(2) + ":" + this.getSeconds().leftPad(2) + "." +
this.getMilliseconds().leftPad(3);
}
Number.prototype.leftPad = function (size) {
var s = String(this);
while (s.length < (size || 2)) {
s = "0" + s;
}
return s;
}
Example usage:
var date = new Date();
console.log(date.toISOLocaleString() + date.getISOTimezoneOffset());
// Prints "2020-08-05T16:15:46.525+10:00"
I know it's 2020 and most people are probably using Moment.js by now, but a simple copy & pastable solution is still sometimes handy to have.
(The reason I split the date/time and offset methods is because I'm using an old Datejs library which already provides a flexible toString method with custom format specifiers, but just doesn't include the timezone offset. Hence, I added toISOLocaleString for anyone without said library.)
Just my two cents here
I was facing this issue with datetimes so what I did is this:
const moment = require('moment-timezone')
const date = moment.tz('America/Bogota').format()
Then save date to db to be able to compare it from some query.
To install moment-timezone
npm i moment-timezone
No moment.js needed: Here's a full round trip answer, from an input type of "datetime-local" which outputs an ISOLocal string to UTCseconds at GMT and back:
<input type="datetime-local" value="2020-02-16T19:30">
isoLocal="2020-02-16T19:30"
utcSeconds=new Date(isoLocal).getTime()/1000
//here you have 1581899400 for utcSeconds
let isoLocal=new Date(utcSeconds*1000-new Date().getTimezoneOffset()*60000).toISOString().substring(0,16)
2020-02-16T19:30
date to ISO string,
with local(computer) time zone,
with or without milliseconds
ISO ref: https://en.wikipedia.org/wiki/ISO_8601
how to use: toIsoLocalTime(new Date())
function toIsoLocalTime(value) {
if (value instanceof Date === false)
value = new Date();
const off = value.getTimezoneOffset() * -1;
const del = value.getMilliseconds() ? 'Z' : '.'; // have milliseconds ?
value = new Date(value.getTime() + off * 60000); // add or subtract time zone
return value
.toISOString()
.split(del)[0]
+ (off < 0 ? '-' : '+')
+ ('0' + Math.abs(Math.floor(off / 60))).substr(-2)
+ ':'
+ ('0' + Math.abs(off % 60)).substr(-2);
}
function test(value) {
const event = new Date(value);
console.info(value + ' -> ' + toIsoLocalTime(event) + ', test = ' + (event.getTime() === (new Date(toIsoLocalTime(event))).getTime() ));
}
test('2017-06-14T10:00:00+03:00'); // test with timezone
test('2017-06-14T10:00:00'); // test with local timezone
test('2017-06-14T10:00:00Z'); // test with UTC format
test('2099-12-31T23:59:59.999Z'); // date with milliseconds
test((new Date()).toString()); // now
consider using moment (like Matt's answer).
From version 2.20.0, you may call .toISOString(true) to prevent UTC conversion:
console.log(moment().toISOString(true));
// sample output: 2022-04-06T16:26:36.758+03:00
Use Temporal.
Temporal.Now.zonedDateTimeISO().toString()
// '2022-08-09T14:16:47.762797591-07:00[America/Los_Angeles]'
To omit the fractional seconds and IANA time zone:
Temporal.Now.zonedDateTimeISO().toString({
timeZoneName: "never",
fractionalSecondDigits: 0
})
// '2022-08-09T14:18:34-07:00'
Note: Temporal is currently (2022) available as a polyfill, but will soon be available in major browsers.
With luxon:
DateTime.now().toISODate() // 2022-05-23
Here are the functions I used for this end:
function localToGMTStingTime(localTime = null) {
var date = localTime ? new Date(localTime) : new Date();
return new Date(date.getTime() + (date.getTimezoneOffset() * 60000)).toISOString();
};
function GMTToLocalStingTime(GMTTime = null) {
var date = GMTTime ? new Date(GMTTime) : new Date();;
return new Date(date.getTime() - (date.getTimezoneOffset() * 60000)).toISOString();
};
let myDate = new Date(dateToBeFormatted * 1000); // depends if you have milliseconds, or seconds, then the * 1000 might be not, or required.
timeOffset = myDate.getTimezoneOffset();
myDate = new Date(myDate.getTime() - (timeOffset * 60 * 1000));
console.log(myDate.toISOString().split('T')[0]);
Inspired by https://stackoverflow.com/a/29774197/11127383, including timezone offset comment.
a simple way to get:
//using a sample date
let iso_str = '2022-06-11T01:51:59.618Z';
let d = new Date(iso_str);
let tz = 'America/Santiago'
let options = {
timeZone:tz ,
timeZoneName:'longOffset',
year: 'numeric',
month: 'numeric',
day: 'numeric',
hour: 'numeric',
minute: 'numeric',
second: 'numeric',
fractionalSecondDigits: 3
}
str_locale = d.toLocaleString("sv-SE",options);
iso_str_tz = str_locale.replace(/(\d{4})-(\d{2})-(\d{2})\s+(\d{2}):(\d{2}):(\d{2}),(\d+)\s+/,'$1-$2-$3T$4:$5:$6.$7').replace('GMT−', '-' ).replace('GMT+','+')
console.log('iso_str : ',iso_str);
console.log('str_locale : ',str_locale);
console.log('iso_str_tz : ',iso_str_tz);
console.log('iso_str_tz --> date : ',new Date(iso_str_tz));
console.log('iso_str_tz --> iso_str: ',new Date(iso_str_tz).toISOString());
Using moment.js, you can use keepOffset parameter of toISOString:
toISOString(keepOffset?: boolean): string;
moment().toISOString(true)
Alternative approach with dayjs
import dayjs from "dayjs"
const formattedDateTime = dayjs(new Date()).format()
console.log(formattedDateTime) // Prints 2022-11-09T07:49:29+03:00
Here's another way a convert your date with an offset.
function toCustomDateString(date, offset) {
function pad(number) {
if (number < 10) {
return "0" + number;
}
return number;
}
var offsetHours = offset / 60;
var offsetMinutes = offset % 60;
var sign = (offset > 0) ? "+" : "-";
offsetHours = pad(Math.floor(Math.abs(offsetHours)));
offsetMinutes = pad(Math.abs(offsetMinutes));
return date.getFullYear() +
"-" + pad(date.getMonth() + 1) +
"-" + pad(date.getDate()) +
"T" + pad(date.getHours()) +
":" + pad(date.getMinutes()) +
":" + pad(date.getSeconds()) +
sign + offsetHours +
":" + offsetMinutes;
}
Then you can use it like this:
var date = new Date();
var offset = 330; // offset in minutes from UTC, for India it is 330 minutes ahead of UTC
var customDateString = toCustomDateString(date, offset);
console.log(customDateString);
// Output: "2023-02-09T10:29:31+05:30"
function setDate(){
var now = new Date();
now.setMinutes(now.getMinutes() - now.getTimezoneOffset());
var timeToSet = now.toISOString().slice(0,16);
/*
If you have an element called "eventDate" like the following:
<input type="datetime-local" name="eventdate" id="eventdate" />
and you would like to set the current and minimum time then use the following:
*/
var elem = document.getElementById("eventDate");
elem.value = timeToSet;
elem.min = timeToSet;
}
I found another more easy solution:
let now = new Date();
// correct time zone offset for generating iso string
now.setMinutes(now.getMinutes() - now.getTimezoneOffset())
now = now.toISOString();
I undo the timezone offset by substracting it from the current date object.
The UTC time from the date object is now pointing to the local time.
That gives you the possibility to get the iso date for the local time.
I have a Date object. How do I render the title portion of the following snippet?
<abbr title="2010-04-02T14:12:07">A couple days ago</abbr>
I have the "relative time in words" portion from another library.
I've tried the following:
function isoDate(msSinceEpoch) {
var d = new Date(msSinceEpoch);
return d.getUTCFullYear() + '-' + (d.getUTCMonth() + 1) + '-' + d.getUTCDate() + 'T' +
d.getUTCHours() + ':' + d.getUTCMinutes() + ':' + d.getUTCSeconds();
}
But that gives me:
"2010-4-2T3:19"
There is already a function called toISOString():
var date = new Date();
date.toISOString(); //"2011-12-19T15:28:46.493Z"
If, somehow, you're on a browser that doesn't support it, I've got you covered:
if (!Date.prototype.toISOString) {
(function() {
function pad(number) {
var r = String(number);
if (r.length === 1) {
r = '0' + r;
}
return r;
}
Date.prototype.toISOString = function() {
return this.getUTCFullYear() +
'-' + pad(this.getUTCMonth() + 1) +
'-' + pad(this.getUTCDate()) +
'T' + pad(this.getUTCHours()) +
':' + pad(this.getUTCMinutes()) +
':' + pad(this.getUTCSeconds()) +
'.' + String((this.getUTCMilliseconds() / 1000).toFixed(3)).slice(2, 5) +
'Z';
};
}());
}
console.log(new Date().toISOString())
Note: This answer is still getting upvotes as of 2022-03. The moment.js library is deprecated. These are the two main alternatives: Luxon and Day.js, others are mentioned in the deprecation link.
Luxon
Luxon can be thought of as the evolution of Moment. It is authored by
Isaac Cambron, a long-time contributor to Moment. Please read Why does
Luxon exist? and the For Moment users pages in the Luxon
documentation.
Locales: Intl provided Time Zones: Intl provided
Day.js
Day.js is designed to be a minimalist replacement for Moment.js, using
a similar API. It is not a drop-in replacement, but if you are used to
using Moment's API and want to get moving quickly, consider using
Day.js.
Locales: Custom data files that can be individually imported Time
Zones: Intl provided, via a plugin
I use Day.js because of the size difference, but Luxon is easier to deal with.
Almost every to-ISO method on the web drops the timezone information by applying a convert to "Z"ulu time (UTC) before outputting the string. Browser's native .toISOString() also drops timezone information.
This discards valuable information, as the server, or recipient, can always convert a full ISO date to Zulu time or whichever timezone it requires, while still getting the timezone information of the sender.
The best solution I've come across is to use the Moment.js javascript library and use the following code:
To get the current ISO time with timezone information and milliseconds
now = moment().format("YYYY-MM-DDTHH:mm:ss.SSSZZ")
// "2013-03-08T20:11:11.234+0100"
now = moment().utc().format("YYYY-MM-DDTHH:mm:ss.SSSZZ")
// "2013-03-08T19:11:11.234+0000"
now = moment().utc().format("YYYY-MM-DDTHH:mm:ss") + "Z"
// "2013-03-08T19:11:11Z" <- better use the native .toISOString()
To get the ISO time of a native JavaScript Date object with timezone information but without milliseconds
var current_time = Date.now();
moment(current_time).format("YYYY-MM-DDTHH:mm:ssZZ")
This can be combined with Date.js to get functions like Date.today() whose result can then be passed to moment.
A date string formatted like this is JSON compilant, and lends itself well to get stored into a database. Python and C# seem to like it.
See the last example on page https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference:Global_Objects:Date:
/* 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();
console.log(ISODateString(d)); // Prints something like 2009-09-28T19:03:12Z
The question asked was ISO format with reduced precision. Voila:
new Date().toISOString().slice(0, 19) + 'Z'
// '2014-10-23T13:18:06Z'
Assuming the trailing Z is wanted, otherwise just omit.
Shortest, but not supported by Internet Explorer 8 and earlier:
new Date().toJSON()
If you don't need to support IE7, the following is a great, concise hack:
console.log(
JSON.parse(JSON.stringify(new Date()))
)
I typically don't want to display a UTC date since customers don't like doing the conversion in their head. To display a local ISO date, I use the function:
function toLocalIsoString(date, includeSeconds) {
function pad(n) { return n < 10 ? '0' + n : n }
var localIsoString = date.getFullYear() + '-'
+ pad(date.getMonth() + 1) + '-'
+ pad(date.getDate()) + 'T'
+ pad(date.getHours()) + ':'
+ pad(date.getMinutes()) + ':'
+ pad(date.getSeconds());
if(date.getTimezoneOffset() == 0) localIsoString += 'Z';
return localIsoString;
};
The function above omits time zone offset information (except if local time happens to be UTC), so I use the function below to show the local offset in a single location. You can also append its output to results from the above function if you wish to show the offset in each and every time:
function getOffsetFromUTC() {
var offset = new Date().getTimezoneOffset();
return ((offset < 0 ? '+' : '-')
+ pad(Math.abs(offset / 60), 2)
+ ':'
+ pad(Math.abs(offset % 60), 2))
};
toLocalIsoString uses pad. If needed, it works like nearly any pad function, but for the sake of completeness this is what I use:
// Pad a number to length using padChar
function pad(number, length, padChar) {
if (typeof length === 'undefined') length = 2;
if (typeof padChar === 'undefined') padChar = '0';
var str = "" + number;
while (str.length < length) {
str = padChar + str;
}
return str;
}
The problem with toISOString is that it gives datetime only as "Z".
ISO-8601 also defines datetime with timezone difference in hours and minutes, in the forms like 2016-07-16T19:20:30+5:30 (when timezone is ahead UTC) and 2016-07-16T19:20:30-01:00 (when timezone is behind UTC).
I don't think it is a good idea to use another plugin, moment.js for such a small task, especially when you can get it with a few lines of code.
Once you have the timezone offset in hours and minutes, you can append to a datetime string.
I wrote a blog post on it : http://usefulangle.com/post/30/javascript-get-date-time-with-offset-hours-minutes
var timezone_offset_min = new Date().getTimezoneOffset(),
offset_hrs = parseInt(Math.abs(timezone_offset_min / 60)),
offset_min = Math.abs(timezone_offset_min % 60),
timezone_standard;
if (offset_hrs < 10)
offset_hrs = '0' + offset_hrs;
if (offset_min > 10)
offset_min = '0' + offset_min;
// getTimezoneOffset returns an offset which is positive if the local timezone is behind UTC and vice-versa.
// So add an opposite sign to the offset
// If offset is 0, it means timezone is UTC
if (timezone_offset_min < 0)
timezone_standard = '+' + offset_hrs + ':' + offset_min;
else if (timezone_offset_min > 0)
timezone_standard = '-' + offset_hrs + ':' + offset_min;
else if (timezone_offset_min == 0)
timezone_standard = 'Z';
// Timezone difference in hours and minutes
// String such as +5:30 or -6:00 or Z
console.log(timezone_standard);
There is a '+' missing after the 'T'
isoDate: function(msSinceEpoch) {
var d = new Date(msSinceEpoch);
return d.getUTCFullYear() + '-' + (d.getUTCMonth() + 1) + '-' + d.getUTCDate() + 'T'
+ d.getUTCHours() + ':' + d.getUTCMinutes() + ':' + d.getUTCSeconds();
}
should do it.
For the leading zeros you could use this from here:
function PadDigits(n, totalDigits)
{
n = n.toString();
var pd = '';
if (totalDigits > n.length)
{
for (i=0; i < (totalDigits-n.length); i++)
{
pd += '0';
}
}
return pd + n.toString();
}
Using it like this:
PadDigits(d.getUTCHours(),2)
function timeStr(d) {
return ''+
d.getFullYear()+
('0'+(d.getMonth()+1)).slice(-2)+
('0'+d.getDate()).slice(-2)+
('0'+d.getHours()).slice(-2)+
('0'+d.getMinutes()).slice(-2)+
('0'+d.getSeconds()).slice(-2);
}
I was able to get below output with very less code.
var ps = new Date('2010-04-02T14:12:07') ;
ps = ps.toDateString() + " " + ps.getHours() + ":"+ ps.getMinutes() + " hrs";
Output:
Fri Apr 02 2010 19:42 hrs
I think I have found an even better solution:
According to the wiki page Canada uses ISO 8601 as the official date format, therefore we can safely use this.
console.log(new Date("2022-12-19 00:43:00 GMT+0100").toISOString().split("T")[0]);
// results in '2022-12-18'
console.log(new Date("2022-12-19 00:43:00 GMT+0100").toLocaleDateString("en-CA"));
// results in '2022-12-19'
I would just use this small extension to Date - http://blog.stevenlevithan.com/archives/date-time-format
var date = new Date(msSinceEpoch);
date.format("isoDateTime"); // 2007-06-09T17:46:21
function getdatetime() {
d = new Date();
return (1e3-~d.getUTCMonth()*10+d.toUTCString()+1e3+d/1)
.replace(/1(..)..*?(\d+)\D+(\d+).(\S+).*(...)/,'$3-$1-$2T$4.$5Z')
.replace(/-(\d)T/,'-0$1T');
}
I found the basics on Stack Overflow somewhere (I believe it was part of some other Stack Exchange code golfing), and I improved it so it works on Internet Explorer 10 or earlier as well. It's ugly, but it gets the job done.
A short one:
console.log(new Date().toISOString().slice(0,19).replace('T', ' '))
To extend Sean's great and concise answer with some sugar and modern syntax:
// date.js
const getMonthName = (num) => {
const months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Oct', 'Nov', 'Dec'];
return months[num];
};
const formatDate = (d) => {
const date = new Date(d);
const year = date.getFullYear();
const month = getMonthName(date.getMonth());
const day = ('0' + date.getDate()).slice(-2);
const hour = ('0' + date.getHours()).slice(-2);
const minutes = ('0' + date.getMinutes()).slice(-2);
return `${year} ${month} ${day}, ${hour}:${minutes}`;
};
module.exports = formatDate;
Then eg.
import formatDate = require('./date');
const myDate = "2018-07-24T13:44:46.493Z"; // Actual value from wherever, eg. MongoDB date
console.log(formatDate(myDate)); // 2018 Jul 24, 13:44
Goal: Find the local time and UTC time offset then construct the URL in following format.
Example URL: /Actions/Sleep?duration=2002-10-10T12:00:00−05:00
The format is based on the W3C recommendation. The documentation says:
For example, 2002-10-10T12:00:00−05:00 (noon on 10 October 2002,
Central Daylight Savings Time as well as Eastern Standard Time in the U.S.)
is equal to 2002-10-10T17:00:00Z, five hours later than 2002-10-10T12:00:00Z.
So based on my understanding, I need to find my local time by new Date() then use getTimezoneOffset() function to compute the difference then attach it to the end of string.
Get local time with format
var local = new Date().format("yyyy-MM-ddThh:mm:ss"); // 2013-07-02T09:00:00
Get UTC time offset by hour
var offset = local.getTimezoneOffset() / 60; // 7
Construct URL (time part only)
var duration = local + "-" + offset + ":00"; // 2013-07-02T09:00:00-7:00
The above output means my local time is 2013/07/02 9am and difference from UTC is 7 hours (UTC is 7 hours ahead of local time)
So far it seems to work but what if getTimezoneOffset() returns negative value like -120?
I'm wondering how the format should look like in such case because I cannot figure out from W3C documentation.
Here's a simple helper function that will format JS dates for you.
function toIsoString(date) {
var tzo = -date.getTimezoneOffset(),
dif = tzo >= 0 ? '+' : '-',
pad = function(num) {
return (num < 10 ? '0' : '') + num;
};
return date.getFullYear() +
'-' + pad(date.getMonth() + 1) +
'-' + pad(date.getDate()) +
'T' + pad(date.getHours()) +
':' + pad(date.getMinutes()) +
':' + pad(date.getSeconds()) +
dif + pad(Math.floor(Math.abs(tzo) / 60)) +
':' + pad(Math.abs(tzo) % 60);
}
var dt = new Date();
console.log(toIsoString(dt));
getTimezoneOffset() returns the opposite sign of the format required by the spec that you referenced.
This format is also known as ISO8601, or more precisely as RFC3339.
In this format, UTC is represented with a Z while all other formats are represented by an offset from UTC. The meaning is the same as JavaScript's, but the order of subtraction is inverted, so the result carries the opposite sign.
Also, there is no method on the native Date object called format, so your function in #1 will fail unless you are using a library to achieve this. Refer to this documentation.
If you are seeking a library that can work with this format directly, I recommend trying moment.js. In fact, this is the default format, so you can simply do this:
var m = moment(); // get "now" as a moment
var s = m.format(); // the ISO format is the default so no parameters are needed
// sample output: 2013-07-01T17:55:13-07:00
This is a well-tested, cross-browser solution, and has many other useful features.
I think it is worth considering that you can get the requested info with just a single API call to the standard library...
new Date().toLocaleString( 'sv', { timeZoneName: 'short' } );
// produces "2019-10-30 15:33:47 GMT−4"
You would have to do text swapping if you want to add the 'T' delimiter, remove the 'GMT-', or append the ':00' to the end.
But then you can easily play with the other options if you want to eg. use 12h time or omit the seconds etc.
Note that I'm using Sweden as locale because it is one of the countries that uses ISO 8601 format. I think most of the ISO countries use this 'GMT-4' format for the timezone offset other then Canada which uses the time zone abbreviation eg. "EDT" for eastern-daylight-time.
You can get the same thing from the newer standard i18n function "Intl.DateTimeFormat()"
but you have to tell it to include the time via the options or it will just give date.
My answer is a slight variation for those who just want today's date in the local timezone in the YYYY-MM-DD format.
Let me be clear:
My Goal: get today's date in the user's timezone but formatted as ISO8601 (YYYY-MM-DD)
Here is the code:
new Date().toLocaleDateString("sv") // "2020-02-23" //
This works because the Sweden locale uses the ISO 8601 format.
This is my function for the clients timezone, it's lite weight and simple
function getCurrentDateTimeMySql() {
var tzoffset = (new Date()).getTimezoneOffset() * 60000; //offset in milliseconds
var localISOTime = (new Date(Date.now() - tzoffset)).toISOString().slice(0, 19).replace('T', ' ');
var mySqlDT = localISOTime;
return mySqlDT;
}
Check this:
function dateToLocalISO(date) {
const off = date.getTimezoneOffset()
const absoff = Math.abs(off)
return (new Date(date.getTime() - off*60*1000).toISOString().substr(0,23) +
(off > 0 ? '-' : '+') +
Math.floor(absoff / 60).toFixed(0).padStart(2,'0') + ':' +
(absoff % 60).toString().padStart(2,'0'))
}
// Test it:
d = new Date()
dateToLocalISO(d)
// ==> '2019-06-21T16:07:22.181-03:00'
// Is similar to:
moment = require('moment')
moment(d).format('YYYY-MM-DDTHH:mm:ss.SSSZ')
// ==> '2019-06-21T16:07:22.181-03:00'
You can achieve this with a few simple extension methods. The following Date extension method returns just the timezone component in ISO format, then you can define another for the date/time part and combine them for a complete date-time-offset string.
Date.prototype.getISOTimezoneOffset = function () {
const offset = this.getTimezoneOffset();
return (offset < 0 ? "+" : "-") + Math.floor(Math.abs(offset / 60)).leftPad(2) + ":" + (Math.abs(offset % 60)).leftPad(2);
}
Date.prototype.toISOLocaleString = function () {
return this.getFullYear() + "-" + (this.getMonth() + 1).leftPad(2) + "-" +
this.getDate().leftPad(2) + "T" + this.getHours().leftPad(2) + ":" +
this.getMinutes().leftPad(2) + ":" + this.getSeconds().leftPad(2) + "." +
this.getMilliseconds().leftPad(3);
}
Number.prototype.leftPad = function (size) {
var s = String(this);
while (s.length < (size || 2)) {
s = "0" + s;
}
return s;
}
Example usage:
var date = new Date();
console.log(date.toISOLocaleString() + date.getISOTimezoneOffset());
// Prints "2020-08-05T16:15:46.525+10:00"
I know it's 2020 and most people are probably using Moment.js by now, but a simple copy & pastable solution is still sometimes handy to have.
(The reason I split the date/time and offset methods is because I'm using an old Datejs library which already provides a flexible toString method with custom format specifiers, but just doesn't include the timezone offset. Hence, I added toISOLocaleString for anyone without said library.)
Just my two cents here
I was facing this issue with datetimes so what I did is this:
const moment = require('moment-timezone')
const date = moment.tz('America/Bogota').format()
Then save date to db to be able to compare it from some query.
To install moment-timezone
npm i moment-timezone
No moment.js needed: Here's a full round trip answer, from an input type of "datetime-local" which outputs an ISOLocal string to UTCseconds at GMT and back:
<input type="datetime-local" value="2020-02-16T19:30">
isoLocal="2020-02-16T19:30"
utcSeconds=new Date(isoLocal).getTime()/1000
//here you have 1581899400 for utcSeconds
let isoLocal=new Date(utcSeconds*1000-new Date().getTimezoneOffset()*60000).toISOString().substring(0,16)
2020-02-16T19:30
date to ISO string,
with local(computer) time zone,
with or without milliseconds
ISO ref: https://en.wikipedia.org/wiki/ISO_8601
how to use: toIsoLocalTime(new Date())
function toIsoLocalTime(value) {
if (value instanceof Date === false)
value = new Date();
const off = value.getTimezoneOffset() * -1;
const del = value.getMilliseconds() ? 'Z' : '.'; // have milliseconds ?
value = new Date(value.getTime() + off * 60000); // add or subtract time zone
return value
.toISOString()
.split(del)[0]
+ (off < 0 ? '-' : '+')
+ ('0' + Math.abs(Math.floor(off / 60))).substr(-2)
+ ':'
+ ('0' + Math.abs(off % 60)).substr(-2);
}
function test(value) {
const event = new Date(value);
console.info(value + ' -> ' + toIsoLocalTime(event) + ', test = ' + (event.getTime() === (new Date(toIsoLocalTime(event))).getTime() ));
}
test('2017-06-14T10:00:00+03:00'); // test with timezone
test('2017-06-14T10:00:00'); // test with local timezone
test('2017-06-14T10:00:00Z'); // test with UTC format
test('2099-12-31T23:59:59.999Z'); // date with milliseconds
test((new Date()).toString()); // now
consider using moment (like Matt's answer).
From version 2.20.0, you may call .toISOString(true) to prevent UTC conversion:
console.log(moment().toISOString(true));
// sample output: 2022-04-06T16:26:36.758+03:00
Use Temporal.
Temporal.Now.zonedDateTimeISO().toString()
// '2022-08-09T14:16:47.762797591-07:00[America/Los_Angeles]'
To omit the fractional seconds and IANA time zone:
Temporal.Now.zonedDateTimeISO().toString({
timeZoneName: "never",
fractionalSecondDigits: 0
})
// '2022-08-09T14:18:34-07:00'
Note: Temporal is currently (2022) available as a polyfill, but will soon be available in major browsers.
With luxon:
DateTime.now().toISODate() // 2022-05-23
Here are the functions I used for this end:
function localToGMTStingTime(localTime = null) {
var date = localTime ? new Date(localTime) : new Date();
return new Date(date.getTime() + (date.getTimezoneOffset() * 60000)).toISOString();
};
function GMTToLocalStingTime(GMTTime = null) {
var date = GMTTime ? new Date(GMTTime) : new Date();;
return new Date(date.getTime() - (date.getTimezoneOffset() * 60000)).toISOString();
};
let myDate = new Date(dateToBeFormatted * 1000); // depends if you have milliseconds, or seconds, then the * 1000 might be not, or required.
timeOffset = myDate.getTimezoneOffset();
myDate = new Date(myDate.getTime() - (timeOffset * 60 * 1000));
console.log(myDate.toISOString().split('T')[0]);
Inspired by https://stackoverflow.com/a/29774197/11127383, including timezone offset comment.
a simple way to get:
//using a sample date
let iso_str = '2022-06-11T01:51:59.618Z';
let d = new Date(iso_str);
let tz = 'America/Santiago'
let options = {
timeZone:tz ,
timeZoneName:'longOffset',
year: 'numeric',
month: 'numeric',
day: 'numeric',
hour: 'numeric',
minute: 'numeric',
second: 'numeric',
fractionalSecondDigits: 3
}
str_locale = d.toLocaleString("sv-SE",options);
iso_str_tz = str_locale.replace(/(\d{4})-(\d{2})-(\d{2})\s+(\d{2}):(\d{2}):(\d{2}),(\d+)\s+/,'$1-$2-$3T$4:$5:$6.$7').replace('GMT−', '-' ).replace('GMT+','+')
console.log('iso_str : ',iso_str);
console.log('str_locale : ',str_locale);
console.log('iso_str_tz : ',iso_str_tz);
console.log('iso_str_tz --> date : ',new Date(iso_str_tz));
console.log('iso_str_tz --> iso_str: ',new Date(iso_str_tz).toISOString());
Using moment.js, you can use keepOffset parameter of toISOString:
toISOString(keepOffset?: boolean): string;
moment().toISOString(true)
Alternative approach with dayjs
import dayjs from "dayjs"
const formattedDateTime = dayjs(new Date()).format()
console.log(formattedDateTime) // Prints 2022-11-09T07:49:29+03:00
Here's another way a convert your date with an offset.
function toCustomDateString(date, offset) {
function pad(number) {
if (number < 10) {
return "0" + number;
}
return number;
}
var offsetHours = offset / 60;
var offsetMinutes = offset % 60;
var sign = (offset > 0) ? "+" : "-";
offsetHours = pad(Math.floor(Math.abs(offsetHours)));
offsetMinutes = pad(Math.abs(offsetMinutes));
return date.getFullYear() +
"-" + pad(date.getMonth() + 1) +
"-" + pad(date.getDate()) +
"T" + pad(date.getHours()) +
":" + pad(date.getMinutes()) +
":" + pad(date.getSeconds()) +
sign + offsetHours +
":" + offsetMinutes;
}
Then you can use it like this:
var date = new Date();
var offset = 330; // offset in minutes from UTC, for India it is 330 minutes ahead of UTC
var customDateString = toCustomDateString(date, offset);
console.log(customDateString);
// Output: "2023-02-09T10:29:31+05:30"
function setDate(){
var now = new Date();
now.setMinutes(now.getMinutes() - now.getTimezoneOffset());
var timeToSet = now.toISOString().slice(0,16);
/*
If you have an element called "eventDate" like the following:
<input type="datetime-local" name="eventdate" id="eventdate" />
and you would like to set the current and minimum time then use the following:
*/
var elem = document.getElementById("eventDate");
elem.value = timeToSet;
elem.min = timeToSet;
}
I found another more easy solution:
let now = new Date();
// correct time zone offset for generating iso string
now.setMinutes(now.getMinutes() - now.getTimezoneOffset())
now = now.toISOString();
I undo the timezone offset by substracting it from the current date object.
The UTC time from the date object is now pointing to the local time.
That gives you the possibility to get the iso date for the local time.