Android get timezone offset

Android how to get UTC Timezone offset even of negative timezone

Hi I am trying to send the UTC offset towards my server. So I am converting the device time zone into utc offset using following code

Now i know as I am using the Math.abs it is not giving me the minus values but I am really dumb to know that how could I get the offset of those timezone who are in negative such as Tijuana which is GMT-07:00

Note: I may be wrong about the offset thing in UTC but this solution I found on SO. Please let me know if there is any solution or also correct me if I am wrong in idea and its that UTC could not be in negative

2 Answers 2

Use SimpleDateFormat to format it for you:

↓↓↓↓↓ IGNORE REST OF ANSWER IF IT IS CONFUSING ↓↓↓↓↓

Results when applying to all TimeZones in the Java VM:

Java 8 code to print the above:

how could I get the offset of those timezone who are in negative such as Tijuana which is GMT-07:00

• No need to do the math yourself. We have classes for this: java.time.
• For older Java before Java 8, use the ThreeTen-Backport library.
  • For older Android, see the ThreeTenABP project.
• Avoid Date , Calendar , SimpleDateFormat , and TimeZone legacy classes.

To get total seconds of that offset, call ZoneOffset::getTotalSeconds .

java.time

The modern approach uses the modern java.time classes. You are using terrible date-time classes that were years ago supplanted by java.time.

Notice that we passed a moment, represented as Instant object (a moment as seen in UTC). Politicians frequently change the offset used by the zone(s) of their jurisdiction. So the offset of your zone is likely to change over time. So you must specify a moment to ask for the offset that was in effect at that point in time.

Generate text representing that offset, using standard ISO 8601 format.

When receiving such text, you can parse as a ZoneOffset object.

that UTC could not be in negative

An negative offset means a place whose clocks run behind UTC. Generally, this means west (left) of the prime meridian, such as the Americas.

A positive offset means a place whose clocks run ahead of UTC. Generally, this means east (right) of the prime meridian, such as Europe, Africa, Asia.

Well, this is the commonly used meaning of positive & negative offsets, defined in the ISO 8601 standard. Some protocols and industries may use the opposite meaning. Always understand the intention of any data source you may be using.

how could I get the offset of those timezone who are in negative such as Tijuana which is GMT-07:00

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date , Calendar , & SimpleDateFormat .

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

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How to get TimeZone from android mobile?

I want to get the time zone from the Android mobile when clicking a button.

12 Answers 12

Have you tried to use TimeZone.getDefault() :

Most applications will use TimeZone.getDefault() which returns a TimeZone based on the time zone where the program is running.

TimeZone GMT+09:30 Timezone id :: Australia/Darwin

Edit: corrected the case

I needed the offset that not only included day light savings time but as a numerial. Here is the code that I used in case someone is looking for an example.

I get a response of «3.5» (3:30′) which is what I would expect in Tehran , Iran in winter and «4.5» (4:30′) for summer .

I also needed it as a string so I could post it to a server so you may not need the last line.

for getting currect time zone :

It will return user selected timezone.

ZoneId from java.time and ThreeTenABP

When I ran this snippet in Australia/Sydney time zone, the output was exactly that:

If you want the summer time (DST) aware time zone name or abbreviation:

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How to get the timezone offset in GMT(Like GMT+7:00) from android device?

I am getting the timezone of a android device using this code

But it always return me the timezone like » IST » but i want to get the timezone in GMT like this GMT+7:00.

22 Answers 22

This might give you an idea on how to implement it to your liking:

(TimeUnit is «java.util.concurrent.TimeUnit»)

This code return me GMT offset.

It returns the time zone offset like this: +0530

If we use SimpleDateFormat below

It returns the time zone offset like this: GMT+05:30

Here is a solution to get timezone offset in GMT+05:30 this format

returns like +03:30

a one line solution is to use the Z symbol like:

where pattern could be:

full reference here:

This is how Google recommends getting TimezoneOffset.

Yet another solution to get timezone offset:

If someone is looking how to represent the GMT as a float number representing hour offset
(for example «GMT-0530» to -5.5), you can use this:

You can do like this:

Generally you cannot translate from a time zone like Asia/Kolkata to a GMT offset like +05:30 or +07:00. A time zone, as the name says, is a place on earth and comprises the historic, present and known future UTC offsets used by the people in that place (for now we can regard GMT and UTC as synonyms, strictly speaking they are not). For example, Asia/Kolkata has been at offset +05:30 since 1945. During periods between 1941 and 1945 it was at +06:30 and before that time at +05:53:20 (yes, with seconds precision). Many other time zones have summer time (daylight saving time, DST) and change their offset twice a year.

Given a point in time, we can make the translation for that particular point in time, though. I should like to provide the modern way of doing that.

java.time and ThreeTenABP

Output when running just now was:

For the default time zone set zone to ZoneId.systemDefault() .

To format the offset with the text GMT use a formatter with OOOO (four uppercase letter O) in the pattern:

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android: timezone offset for «Europe/Russia» [duplicate]

I need an offset for «Europe/Russia» to UTC.. in hours. here is my code:

For UTC it should be -4 hours. BUT! some user got 3 hours difference!!

I think, the problem is, Russia doesn’t use winter time. And some devices now that, but some not.. how could I implement allway to get «-4» hours?

1 Answer 1

First, Russia isn’t UTC-4.

The problem has to do with Russia not having daylight saving time. But your issue is probably only happening with android 2.x device and less. The daylight saving time was removed before 4.x as far as I remember (if it’s a user input). On the other hand, if you receive a date that was created by the device without user input, you don’t have to convert it as it’s already as UTC.

But as I said, Russia isn’t -4. Russia/Moscow will be +4 hours. But Russia is larger than Moscow really!

So what you’ll have to do is to check if we’re in winter and that the TimeZone is one of those. If the timezone is one of those, you can add one more hour when you want to show. And remove 1 hour when you want to convert to UTC.

I don’t believe it’s possible to update the TimeZone on the android phones and that also means that it’s not exactly possible to do that unless you find an alternative library for Dates that has timezones built-in and which are updated.

You could subclass the DateObject with the functions that you use to behave just like the old date object, all you’ll have to do is to make sure it behaves differently on android2.x and not on android 4.x+.

I checked there and I guess it could be usable and less hacky than my suggestion above. The TimeZones are up to date so it could just work for every phone since it shouldn’t use the internal timezones. On the other hand, if you have functions that require the Date, it might get tricky.

My suggestion is make sure you use UTC everywhere and use JodaTime to format the date with timezones and to do «datetime» operations. If you make sure that your Java Date never contain a TimeZone other than UTC. It should work.

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How to get the timezone offset in GMT(Like GMT+7:00) from android device?

Posted by: admin February 23, 2018 Leave a comment

I am getting the timezone of a android device using this code

But it always return me the timezone like “ IST ” but i want to get the timezone in GMT like this GMT+7:00.

This might give you an idea on how to implement it to your liking:

(TimeUnit is “java.util.concurrent.TimeUnit”)

This code return me GMT offset.

It returns the time zone offset like this: +0530

If we use SimpleDateFormat below

It returns the time zone offset like this: GMT+05:30

Here is a solution to get timezone offset in GMT+05:30 this format

returns like +03:30

Yet another solution to get timezone offset:

a one line solution is to use the Z symbol like:

where pattern could be:

full reference here:

You can do like this:

See if this helps рџ™‚

If someone is looking how to represent the GMT as a float number representing hour offset

(for example “GMT-0530” to -5.5), you can use this:

I’ve been looking at this too and trying to work out how to apply timezone and DST. Here’s my code.

This seems to work, but is there a better way to get the actual time off the device which represents a time that is meaningful and accurate to the user?

I stumbled upon a simple solution for this in Java8 (non-Android) using the ZoneDateTime class. There may be other classes that implement the TemporalAccessor interface that work, but I haven’t found them. This won’t work with standard Date , DateTime , LocalDateTime , and Calender classes as far as I can tell.

The nice thing about this solution is that it avoids a lot of modulo math, string generation, and parsing.

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