In this tutorial, we will learn how to work with timezone in Python.
After reading this article, you’ll learn:
- Handling of timezone by creating a timezone aware date and time.
- How to get the current time in a different timezone
- Get the current timezone name, UTC offset, and DST offset if DST is in effect
- How to convert UTC Datetime to a specific timezone
- Convert time from one timezone to another
- Mathematical operations on two timezone-aware and timezone naive objects
- Learn the tzinfo implementation modules namely pytz, ZoneInfo, and their methods.
Table of contents
What is timezone in Python?
A time zone represents the standardized time depending on which part of the world is being considered.
In simple terms, timezone refers to the local time of a region. UTC (Coordinated Universal Time) is the astronomical time based on earth’s rotation, is the standard against which the world’s region-based time is coordinated.
Note: UTC – Coordinated Universal Time is the common time standard across the world. So, in Python, to work with the timezone without any issues, it is recommended to use the UTC as your base timezone
For example, CT(Central Time) in North and South America is either 5 or 6 hours behind and represented as UTC-5 or UTC-6 based on the Day Light Saving. Below are a few examples.
UTC Offset | Locations | Name | Location |
---|---|---|---|
UTC +9 | Japan, South Korea, and 5 more | JST | Tokyo |
UTC +5:30 | India | IST | India |
UTC +1 | The United Kingdom and 20 more | BST | London |
UTC -10 | Hawaii/USA and 2 more | HST | Honolulu |
Python provides the datetime.tzinfo
abstract base class which provides methods to handle timezone. But this class is an abstract base class and should not be instantiated directly. We need to define a subclass of tzinfo to capture information about a particular time zone.
The pytz library has implemented a timezone class for handling arbitrary fixed offsets from UTC and timezones. This library allows accurate and cross-platform timezone calculations and also solves the issue of ambiguous times at the end of daylight saving time.
pytz is a concrete implementation of the abstract base class tzinfo and is used to create timezone-aware datetime objects.
For example, The datetime.now()
function returns the current local date-time without any timezone information. Using the pytz library, we can pass the timezone name to this function to get the current datetime in the given timezone.
We’ll use the following attributes and methods of the pytz module to work with timezone in Python.
pytz.utc
: Get the standard UTC timezonepytz.timezone('region')
: Create the timezone object of a particular regionpytz.astimezone()
: Convert the time of a particular time zone into another time zone
Create Timezone Aware Datetime Object
In Python, a date object can be mentioned with or without timezones. Based on that, an object is known as Naive or Aware. A date object, by default, is naive. A datetime or time object is aware if it holds the timezone(tz) value.
Follow the below steps to create a timezone aware Datetime Object in Python: –
- Install pytz module if not installed using the
pip install pytz
command. - Use the
pytz.timezone('region_name')
function to create the timezone object - Use the
datetime.now(timezone_obj)
ordatetime.datetime('timezone')
function to create the timezone aware current datetime.

Example:
from datetime import datetime
import pytz
# current Datetime
unaware = datetime.now()
print('Timezone naive:', unaware)
# Standard UTC timezone aware Datetime
aware = datetime.now(pytz.utc)
print('Timezone Aware:', aware)
# US/Central timezone datetime
aware_us_central = datetime.now(pytz.timezone('US/Central'))
print('US Central DateTime', aware_us_central)
Output:
Timezone naive: 2021-07-09 13:22:02.256978
Timezone Aware: 2021-07-09 07:52:02.256978+00:00
US Central DateTime 2021-07-09 02:52:02.313026-05:00
- To get the UTC time we used the
pytz.utc
as a parameter todatetime.now()
function. The offset at the end is +00:00 which is the standrad UTC offset. - To get the CDT datetime, we used the ‘US/Central’ region to create a timezone. The offset at the end is -05:00 is the UTC offset of the CDT region
Refer to list all timezones in Python if you don’t know the exact name of the timezone to create a date and time in the right timezone.
To make the old/existing datetime timezone aware, use the following code.
from datetime import datetime
import pytz
unaware = datetime(2021, 6, 15, 8, 45, 17, 5)
print('Timezone naive:', unaware)
# Convert unaware Datetime to UTC timezone aware Datetime
aware = unaware.replace(tzinfo=pytz.UTC)
print(aware)
Note: The datetime.replace()
method return the new datetime
instance.
Format UTC DateTime to Get the timezone name
Extract the timezone name from UTC DateTime using the DateTime formatting in Python. Use the %Z
directive to get the timezone name.
from datetime import datetime
import pytz
datetime_india = datetime.now(pytz.timezone('Asia/Kolkata'))
print("Formatted DateTime in IST : ", datetime_india.strftime('%Y:%m:%d %H:%M:%S %Z %z'))
# Output 2021:07:08 17:53:23 IST +0530
Note: IST is the timezone name
Create TimeZone Aware Datetime Object Using timezone class
Let’s see how create a timezone aware datetime
object without pytz.
The datetime modules have the timezone
class, which in turn is the subclass of the abstract base class tzinfo
. Each instance created of the timezone class represents the offset of the timezone from the Coordinated Universal Time (UTC).
We can create an UTC-aware datetime
object by assigning the timezone.utc
Syntax:
datetime.timezone(offset, name=None)
Here offset
represents the difference between the local time and the UTC (Coordinated Universal Time). It can be a time delta object ranging from hours=-24 to +24.
Example:
from datetime import datetime, timezone, timedelta
# naive
naive = datetime.now()
print("Naive DateTime:", naive)
# UTC aware
UTC = datetime.now(timezone.utc)
print("UTC DateTime", UTC)
# Creating a datetime with JST (Japan) TimeZone
jst_dateTime = datetime.now(timezone(timedelta(hours=+9), 'JST'))
print("In JST::", jst_dateTime)
Note: we are setting the UTC offset using the timedelta class timedelta(hours=+9)
Get Current Time in Different Timezone
Using the pytz module we can get the current date and time of any timezone.
Syntax:
datetime.now(pytz.timezone('timezone name'))
Steps:
- Use the
pytz.timezone('region_name')
function to create the timezone object - Use
datetime.now(timezone_obj)
function to get the current datetime of the given timezone.
Note: UTC – Coordinated Universal Time is the common time standard across the world. So, to work with the timezone without any issues, it is recommended to use the UTC as your base timezone.
In this example, we’ll see how to get the current datetime in the following timezones
USA: Get current Date and Time in the following TimeZones of United States
from datetime import datetime
import pytz
dt_us_central = datetime.now(pytz.timezone('America/Mexico_City'))
print("US Central DateTime:", dt_us_central.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
dt_us_pacific = datetime.now(pytz.timezone('America/Tijuana'))
print("US Pacific timezone DateTime:", dt_us_pacific.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
dt_us_eastern = datetime.now(pytz.timezone('America/New_York'))
print("US Eastern timezone DateTime:", dt_us_eastern.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
dt_us_mountain = datetime.now(pytz.timezone('America/Chihuahua'))
print("US Mountain timezone DateTime:", dt_us_mountain.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
Output:
US Central DateTime: 2021:07:08 08:37:34 CDT -0500 US Pacific timezone DateTime: 2021:07:08 06:37:34 PDT -0700 US Eastern timezone DateTime: 2021:07:08 09:37:34 EDT -0400 US Mountain timezone DateTime: 2021:07:08 07:37:34 MDT -0600
Other TimeZones
from datetime import datetime
import pytz
dt_japan = datetime.now(pytz.timezone('Asia/Tokyo'))
print("Japan DateTime:", dt_japan.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
dt_brazil = datetime.now(pytz.timezone('America/Sao_Paulo'))
print("Brazil DateTime:", dt_brazil.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
dt_uk = datetime.now(pytz.timezone('Europe/London'))
print("Uk DateTime:", dt_uk.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
dt_germany = datetime.now(pytz.timezone('Europe/Berlin'))
print("Germany DateTime:", dt_germany.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
dt_aus = datetime.now(pytz.timezone('Australia/Canberra'))
print("Australia Oceanic DateTime:", dt_aus.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
dt_africa = datetime.now(pytz.timezone('Africa/Maputo'))
print("Central Africa: DateTime:", dt_africa.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
Output:
Japan DateTime: 2021:07:09 12:02:38 JST +0900 Brazil DateTime: 2021:07:09 00:02:38 -03 -0300 Uk DateTime: 2021:07:09 04:02:38 BST +0100 Germany DateTime: 2021:07:09 05:02:38 CEST +0200 Australia Oceanic DateTime: 2021:07:09 13:02:38 AEST +1000 Central Africa: DateTime: 2021:07:09 05:02:38 CAT +0200
Also, see: Convert between timezones
Get TimeZone Information Using tzinfo
The datetime.tzinfo
is an abstract base class containing information about the date or time object passed to them.
The tzinfo generally contains the following information: –
- The time zone name of a Datetime
- Offset from the UTC (Coordinated Universal Time)
- The DST(Daylight saving).
The tzinfo class provides the following method to get the timezone information: –
tzinfo.tzname(dt)
: Returns the time zone name corresponding to thedatetime
objectdt
. This method returns the name that is used while creating the timezone objecttzinfo.utcoffset(dt)
: This method returns the total offset from the UTC which should be a timedelta object. The values of the timedelta is positive if it is east of UTC and negative for the west of UTC. The total offset includes both timezone and the DST(Day light savings) values. The range of the timedelta is therfore between -timedelta(hours=24) to timedelta(hours=24)tzinfo.dst(dt)
: This method returns dst offset in the zones where dst is in effect. In other cases it will return onlytimedelta(0)
. The dst information is already part of the the utcoffset therefore the tz.utcoffset(dt) - tz.dst(dt)
should return the standard offset of the timezone irrespective of the date and time but only on the geographic location.
Example:
from datetime import datetime
import pytz
# timezone: US Central Time
dt_us_central = datetime.now(pytz.timezone('America/Mexico_City'))
print("US Central DateTime:", dt_us_central.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
# Get current TimeZone name
print(dt_us_central.tzname())
# Get UTC Offset
print(dt_us_central.utcoffset())
# Get the daylight saving time (DST offset) adjustment
print(dt_us_central.dst())
Our code produced the following information:
US Central DateTime: 2021:07:08 22:30:06 CDT -0500 TimeZone Name: CDT UTC Offset -1 day, 19:00:00 DST: 1:00:00
The datetime modules have the timezone
class, which in turn is the subclass of the abstract base class tzinfo
Converting Between Timezones
Use the datetime.astimezone()
method to convert the datetime from one timezone to another. This method uses an instance of the datetime object and returns a new datetime of a given timezone.
import datetime
import pytz
# UTC timezone Datetime
dt_local = datetime.datetime.now(pytz.utc)
print("UTC DateTime:", dt_local.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
# convert UTC timezone to 'US/Central'
dt_us_central = dt_local.astimezone(pytz.timezone('US/Central'))
print("US Central DateTime:", dt_us_central.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
# Convert 'US/Central' timezone to US/Eastern
dt_us_eastern = dt_us_central.astimezone(pytz.timezone('America/New_York'))
print("US Eastern DateTime:", dt_us_eastern.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
# Convert US/Eastern timezone to IST (India) timezone
dt_ind = dt_us_eastern.astimezone(pytz.timezone('Asia/Kolkata'))
print("India DateTime:", dt_ind.strftime("%Y:%m:%d %H:%M:%S %Z %z"))
Output:
UTC DateTime: 2021:07:09 07:19:02 UTC +0000 US Central DateTime: 2021:07:09 02:19:02 CDT -0500 US Eastern DateTime: 2021:07:09 03:19:02 EDT -0400 India DateTime: 2021:07:09 12:49:02 IST +0530
Working with Local Timezones
Note: To work with the timezone without any issues, it is recommended to use the UTC as your base timezone not a local time.
As already mentioned, we can convert a naive datetime to an aware datetime instance with a timezone value set to a local standardized value.
We can do it with one of the pytz
methods called localize
() .This method is used to convert a naive to local time. It accepts the two arguments, namely the datetime object to localize and an optional is_dst
flag.
This flag is set to true if we want to localize and the daylight saving information and false if we want only the standard offset time and false otherwise.
As mentioned above the tzinfo
has a method called dst()
which will return the Daylight Saving Time(DST) information if the flag is set to true.
Let us see an example to show how we can set a local time zone and get the DST information.
from datetime import datetime
import pytz
fmt = '%Y-%m-%d %H:%M:%S %Z%z'
# Indian Standard Time
tz_india = pytz.timezone('Asia/Kolkata')
ist_local = tz_india.localize(datetime.now())
print("Indian Standard Time::", ist_local.strftime(fmt))
# Europe/Amsterdam Time
amdam_tz = pytz.timezone('Europe/Amsterdam')
dt = datetime(1983, 8, 3, 2, 0, 0)
cest_local = amdam_tz.localize(dt, is_dst=True)
print("Amsterdam with daylight saving time::", cest_local.strftime(fmt))
# Day Light Saving
print("Daylight saving time in amsterdam on 3/8/83::", cest_local.tzinfo.dst(cest_local))
Output
Indian Standard Time:: 2021-03-09 14:04:37 IST+0530 Amsterdam with daylight saving time:: 1983-08-03 02:00:00 CEST+0200 Daylight saving time in amsterdam on 3/8/83:: 1:00:00