Java – Convert date and time between timezone

In this tutorial, we will show you few examples (ZonedDateTime (Java 8), Date, Calendar and Joda Time) to convert a date and time between different time zones.

All examples will be converting the date and time from

(UTC+8:00) Asia/Singapore - Singapore TimeDate : 22-1-2015 10:15:55 AM

to

(UTC-5:00) America/New_York - Eastern Standard TimeDate : 21-1-2015 09:15:55 PM

Which to use?
For time zone, avoid both Date and Calendar

1. If you are using JDK >= 8, use the new java.time.* framework.
2. If you are using JDK < 8, use Joda Time. (The new Java 8 java.time.* framework is inspired by this library)

1. ZonedDateTime

Always use this new Java 8 java.time.ZonedDateTime to represent a date and time containing time zone.

ZonedDateTimeExample.java

package com.mkyong.date;import java.time.LocalDateTime;import java.time.ZoneId;import java.time.ZonedDateTime;import java.time.format.DateTimeFormatter;public class ZonedDateTimeExample {    private static final String DATE_FORMAT = "dd-M-yyyy hh:mm:ss a";    public static void main(String[] args) {        String dateInString = "22-1-2015 10:15:55 AM";        LocalDateTime ldt = LocalDateTime.parse(dateInString, DateTimeFormatter.ofPattern(DATE_FORMAT));        ZoneId singaporeZoneId = ZoneId.of("Asia/Singapore");        System.out.println("TimeZone : " + singaporeZoneId);        //LocalDateTime + ZoneId = ZonedDateTime        ZonedDateTime asiaZonedDateTime = ldt.atZone(singaporeZoneId);        System.out.println("Date (Singapore) : " + asiaZonedDateTime);        ZoneId newYokZoneId = ZoneId.of("America/New_York");        System.out.println("TimeZone : " + newYokZoneId);        ZonedDateTime nyDateTime = asiaZonedDateTime.withZoneSameInstant(newYokZoneId);        System.out.println("Date (New York) : " + nyDateTime);        DateTimeFormatter format = DateTimeFormatter.ofPattern(DATE_FORMAT);        System.out.println("\n---DateTimeFormatter---");        System.out.println("Date (Singapore) : " + format.format(asiaZonedDateTime));        System.out.println("Date (New York) : " + format.format(nyDateTime));    }}

Output

TimeZone : Asia/SingaporeDate (Singapore) : 2015-01-22T10:15:55+08:00[Asia/Singapore]TimeZone : America/New_YorkDate (New York) : 2015-01-21T21:15:55-05:00[America/New_York]---DateTimeFormatter---Date (Singapore) : 22-1-2015 10:15:55 AMDate (New York) : 21-1-2015 09:15:55 PM

Note
Refer to this ZonedDateTime tutorial for more time zone, custom offset and daylight saving time (DST) examples.

2. Date

Note
The java.util.Date has no concept of time zone, and only represents the number of seconds passed since the Unix epoch time – 1970-01-01T00:00:00Z. But, if you print the Date object directly, the Date object will be always printed with the default system time zone. Check the Date.toString() source code.

2.1 Set a time zone to DateFormat and format the java.util.Date

SimpleDateFormat sdfAmerica = new SimpleDateFormat("dd-M-yyyy hh:mm:ss a");sdfAmerica.setTimeZone(TimeZone.getTimeZone("America/New_York"));String sDateInAmerica = sdfAmerica.format(date);

2.2 Full example

DateExample.java

package com.mkyong.date;import java.text.ParseException;import java.text.SimpleDateFormat;import java.util.Date;import java.util.TimeZone;public class DateExample {    private static final String DATE_FORMAT = "dd-M-yyyy hh:mm:ss a";    public static void main(String[] args) throws ParseException {        SimpleDateFormat formatter = new SimpleDateFormat(DATE_FORMAT);        String dateInString = "22-01-2015 10:15:55 AM";        Date date = formatter.parse(dateInString);        TimeZone tz = TimeZone.getDefault();        // From TimeZone Asia/Singapore        System.out.println("TimeZone : " + tz.getID() + " - " + tz.getDisplayName());        System.out.println("TimeZone : " + tz);        System.out.println("Date (Singapore) : " + formatter.format(date));        // To TimeZone America/New_York        SimpleDateFormat sdfAmerica = new SimpleDateFormat(DATE_FORMAT);        TimeZone tzInAmerica = TimeZone.getTimeZone("America/New_York");        sdfAmerica.setTimeZone(tzInAmerica);        String sDateInAmerica = sdfAmerica.format(date); // Convert to String first        Date dateInAmerica = formatter.parse(sDateInAmerica); // Create a new Date object        System.out.println("\nTimeZone : " + tzInAmerica.getID() + " - " + tzInAmerica.getDisplayName());        System.out.println("TimeZone : " + tzInAmerica);        System.out.println("Date (New York) (String) : " + sDateInAmerica);        System.out.println("Date (New York) (Object) : " + formatter.format(dateInAmerica));    }}

Output

TimeZone : Asia/Kuala_Lumpur - Malaysia TimeTimeZone : sun.util.calendar.ZoneInfo[id="Asia/Kuala_Lumpur",...]Date (Singapore) : 22-1-2015 10:15:55 AMTimeZone : America/New_York - Eastern Standard TimeTimeZone : sun.util.calendar.ZoneInfo[id="America/New_York",...]Date (New York) (String) : 21-1-2015 09:15:55 PMDate (New York) (Object) : 21-1-2015 09:15:55 PM

3. Calendar

3.1 A Calendar example to set a time zone :

Calendar calendar = new GregorianCalendar();calendar.setTime(date);calendar.setTimeZone(tzInAmerica);

A super common mistake is to get the java.util.Date directly like this :

//Wrong, it will display 22-1-2015 10:15:55 AM, time is still in the system default time zone!Date dateInAmerican = calendar.getTime());

In the above example, no matter what time zone you set in the Calendar, the Date object will be always printed with the default system time zone. (Check the Date.toString() source code)

3.2 The correct way should be using the DateFormat to format it :

SimpleDateFormat sdfAmerica = new SimpleDateFormat("dd-M-yyyy hh:mm:ss a");TimeZone tzInAmerica = TimeZone.getTimeZone("America/New_York");sdfAmerica.setTimeZone(tzInAmerica);sdfAmerica.format(calendar.getTime())

or get the Date via calendar.get() :

int year = calendar.get(Calendar.YEAR);int month = calendar.get(Calendar.MONTH); // Jan = 0, dec = 11int dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH);int hour = calendar.get(Calendar.HOUR); // 12 hour clockint hourOfDay = calendar.get(Calendar.HOUR_OF_DAY); // 24 hour clockint minute = calendar.get(Calendar.MINUTE);int second = calendar.get(Calendar.SECOND);int ampm = calendar.get(Calendar.AM_PM); //0 = AM , 1 = PM

3.3 Full example

CalendarExample.java

package com.mkyong.date;import java.text.ParseException;import java.text.SimpleDateFormat;import java.util.Calendar;import java.util.Date;import java.util.GregorianCalendar;import java.util.TimeZone;public class CalendarExample {    private static final String DATE_FORMAT = "dd-M-yyyy hh:mm:ss a";    public static void main(String[] args) throws ParseException {        SimpleDateFormat formatter = new SimpleDateFormat(DATE_FORMAT);        String dateInString = "22-01-2015 10:15:55 AM";        Date date = formatter.parse(dateInString);        TimeZone tz = TimeZone.getDefault();        // From TimeZone Asia/Singapore        System.out.println("TimeZone : " + tz.getID() + " - " + tz.getDisplayName());        System.out.println("TimeZone : " + tz);        System.out.println("Date (Singapore) : " + formatter.format(date));        // To TimeZone America/New_York        SimpleDateFormat sdfAmerica = new SimpleDateFormat(DATE_FORMAT);        TimeZone tzInAmerica = TimeZone.getTimeZone("America/New_York");        sdfAmerica.setTimeZone(tzInAmerica);        Calendar calendar = new GregorianCalendar();        calendar.setTime(date);        calendar.setTimeZone(tzInAmerica);        System.out.println("\nTimeZone : " + tzInAmerica.getID() + " - " + tzInAmerica.getDisplayName());        System.out.println("TimeZone : " + tzInAmerica);        //Wrong! It will print the date with the system default time zone        System.out.println("Date (New York) (Wrong!): " + calendar.getTime());        //Correct! need formatter        System.out.println("Date (New York) (Correct!) : " + sdfAmerica.format(calendar.getTime()));        int year = calendar.get(Calendar.YEAR);        int month = calendar.get(Calendar.MONTH); // Jan = 0, dec = 11        int dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH);        int hour = calendar.get(Calendar.HOUR); // 12 hour clock        int hourOfDay = calendar.get(Calendar.HOUR_OF_DAY); // 24 hour clock        int minute = calendar.get(Calendar.MINUTE);        int second = calendar.get(Calendar.SECOND);        int ampm = calendar.get(Calendar.AM_PM); //0 = AM , 1 = PM        //Correct        System.out.println("\nyear \t\t: " + year);        System.out.println("month \t\t: " + month + 1);        System.out.println("dayOfMonth \t: " + dayOfMonth);        System.out.println("hour \t\t: " + hour);        System.out.println("minute \t\t: " + minute);        System.out.println("second \t\t: " + second);        System.out.println("ampm \t\t: " + ampm);    }}

Output

TimeZone : Asia/Kuala_Lumpur - Malaysia TimeTimeZone : sun.util.calendar.ZoneInfo[id="Asia/Kuala_Lumpur",...]Date (Singapore) : 22-1-2015 10:15:55 AMTimeZone : America/New_York - Eastern Standard TimeTimeZone : sun.util.calendar.ZoneInfo[id="America/New_York",...]]Date (New York) (Wrong!): Thu Jan 22 10:15:55 MYT 2015Date (New York) (Correct!) : 21-1-2015 09:15:55 PMyear : 2015month : 01dayOfMonth : 21hour : 9minute : 15second : 55ampm : 1

4. Joda Time

4.1 A Joda Time example to set a time zone :

DateTime dt = new DateTime(date);DateTimeZone dtZone = DateTimeZone.forID("America/New_York");DateTime dtus = dt.withZone(dtZone);

Again, a common mistake is getting the Date directly like this, time zone will be lost.

//Output : 22-1-2015 10:15:55 AMDate dateInAmerica = dtus.toDate();

The correct way is converted to Joda LocalDateTime first.

//Output : 21-1-2015 09:15:55 PMDate dateInAmerica = dtus.toLocalDateTime().toDate();

4.2 Full example

JodaTimeExample.java

package com.mkyong.date;import org.joda.time.DateTime;import org.joda.time.DateTimeZone;import java.text.ParseException;import java.text.SimpleDateFormat;import java.util.Date;import java.util.TimeZone;public class JodaTimeExample {    private static final String DATE_FORMAT = "dd-M-yyyy hh:mm:ss a";    public static void main(String[] args) throws ParseException {        SimpleDateFormat formatter = new SimpleDateFormat(DATE_FORMAT);        String dateInString = "22-01-2015 10:15:55 AM";        Date date = formatter.parse(dateInString);        TimeZone tz = TimeZone.getDefault();        // From TimeZone Asia/Singapore        System.out.println("TimeZone : " + tz.getID() + " - " + tz.getDisplayName());        System.out.println("TimeZone : " + tz);        System.out.println("Date (Singapore) : " + formatter.format(date));        // To TimeZone America/New_York        SimpleDateFormat sdfAmerica = new SimpleDateFormat(DATE_FORMAT);        DateTime dt = new DateTime(date);        DateTimeZone dtZone = DateTimeZone.forID("America/New_York");        DateTime dtus = dt.withZone(dtZone);        TimeZone tzInAmerica = dtZone.toTimeZone();        Date dateInAmerica = dtus.toLocalDateTime().toDate(); //Convert to LocalDateTime first        sdfAmerica.setTimeZone(tzInAmerica);        System.out.println("\nTimeZone : " + tzInAmerica.getID() + " - " + tzInAmerica.getDisplayName());        System.out.println("TimeZone : " + tzInAmerica);        System.out.println("DateTimeZone : " + dtZone);        System.out.println("DateTime : " + dtus);        System.out.println("dateInAmerica (Formatter) : " + formatter.format(dateInAmerica));        System.out.println("dateInAmerica (Object) : " + dateInAmerica);    }}

Output

TimeZone : Asia/Kuala_Lumpur - Malaysia TimeTimeZone : sun.util.calendar.ZoneInfo[id="Asia/Kuala_Lumpur",...]Date (Singapore) : 22-1-2015 10:15:55 AMTimeZone : America/New_York - Eastern Standard TimeTimeZone : sun.util.calendar.ZoneInfo[id="America/New_York",...]DateTimeZone : America/New_YorkDateTime : 2015-01-21T21:15:55.000-05:00dateInAmerica (Formatter) : 21-1-2015 09:15:55 PMdateInAmerica (Object) : Wed Jan 21 21:15:55 MYT 2015

http://www.mkyong.com/java/java-convert-date-and-time-between-timezone/

https://www.mkyong.com/java/java-display-list-of-timezone-with-gmt/

http://www.mkyong.com/java8/java-display-all-zoneid-and-its-utc-offset/