Convert date to another timezone in JavaScript

Question

I am looking for a function to convert date in one timezone to another.

It need two parameters,

• date (in format \"2012/04/10 10:10:30 +0000\")

Answer 1

Having looked around a lot including links from this page i found this great article, using moment timezone:

https://www.webniraj.com/2016/11/23/javascript-using-moment-js-to-display-dates-times-in-users-timezone/

To summarise it:

Get the user's timezone

var tz = moment.tz.guess();
console.info('Timezone: ' + tz);

Returns eg: Timezone: Europe/London

Set the default user timezone

moment.tz.setDefault(tz);

Set custom timezone

moment.tz.setDefault('America/Los_Angeles');

Convert date / time to local timezone, assumes original date/time is in UTC

moment.utc('2016-12-25 07:00').tz(tz).format('ffffd, Do MMMM YYYY, h:mma');

Returns: Sun, 25th December 2016, 7:00am

Convert date/time to LA Time

moment.utc('2016-12-25 07:00').tz('America/Los_Angeles').format('ffffd, Do MMMM YYYY, h:mma');

Returns: Sat, 24th December 2016, 11:00pm

Convert from LA time to London

moment.tz('2016-12-25 07:00', 'America/Los_Angeles').tz('Europe/London').format( 'ffffd, Do MMMM YYYY, h:mma' );

Returns: Sun, 25th December 2016, 3:00pm

Answer 2

quick and dirty manual hour changer and return:

return new Date(new Date().setHours(new Date().getHours()+3)).getHours()

Answer 3

If you don't want to import some big library you could just use Intl.DateTimeFormat to convert Date objects to different timezones.

// Specifying timeZone is what causes the conversion, the rest is just formatting
const options = {
  year: '2-digit', month: '2-digit', day: '2-digit',
  hour: '2-digit', minute: '2-digit', second: '2-digit',
  timeZone: 'Asia/Jakarta',
  timeZoneName: 'short'
}
const formatter = new Intl.DateTimeFormat('sv-SE', options)
const startingDate = new Date("2012/04/10 10:10:30 +0000")

const dateInNewTimezone = formatter.format(startingDate) 
console.log(dateInNewTimezone) // 12-04-10 17:10:30 GMT+7

Offsets, daylight saving, and changes in the past will be taken care of for you.

Answer 4

Time Zone Offset for your current timezone

date +%s -d '1 Jan 1970'

For my GMT+10 timezone (Australia) it returned -36000

Answer 5

For moment.js users, you can now use moment-timezone. Using it, your function would look something like this:

function toTimeZone(time, zone) {
    var format = 'YYYY/MM/DD HH:mm:ss ZZ';
    return moment(time, format).tz(zone).format(format);
}

Answer 6

var aestTime = new Date().toLocaleString("en-US", {timeZone: "Australia/Brisbane"});
console.log('AEST time: '+ (new Date(aestTime)).toISOString())

var asiaTime = new Date().toLocaleString("en-US", {timeZone: "Asia/Shanghai"});
console.log('Asia time: '+ (new Date(asiaTime)).toISOString())

var usaTime = new Date().toLocaleString("en-US", {timeZone: "America/New_York"});
console.log('USA time: '+ (new Date(usaTime)).toISOString())

var indiaTime = new Date().toLocaleString("en-US", {timeZone: "Asia/Kolkata"});
console.log('India time: '+ (new Date(indiaTime)).toISOString())

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleString