How to convert local time string to UTC?

Question

How do I convert a datetime string in local time to a string in UTC time?

I\'m sure I\'ve done this before, but can\'t find it and SO will hopefull

Answer 1

In python3:

pip install python-dateutil

from dateutil.parser import tz

mydt.astimezone(tz.gettz('UTC')).replace(tzinfo=None) 

Answer 2

import time

import datetime

def Local2UTC(LocalTime):

    EpochSecond = time.mktime(LocalTime.timetuple())
    utcTime = datetime.datetime.utcfromtimestamp(EpochSecond)

    return utcTime

>>> LocalTime = datetime.datetime.now()

>>> UTCTime = Local2UTC(LocalTime)

>>> LocalTime.ctime()

'Thu Feb  3 22:33:46 2011'

>>> UTCTime.ctime()

'Fri Feb  4 05:33:46 2011'

Answer 3

def local_to_utc(t):
    secs = time.mktime(t)
    return time.gmtime(secs)

def utc_to_local(t):
    secs = calendar.timegm(t)
    return time.localtime(secs)

Source: http://feihonghsu.blogspot.com/2008/02/converting-from-local-time-to-utc.html

Example usage from bd808: If your source is a datetime.datetime object t, call as:

local_to_utc(t.timetuple())

Answer 4

This thread seems to be missing an option available since Python 3.6: datetime.astimezone(tz=None) can be used to get an aware datetime object representing local time (docs). This can then easily be converted to UTC.

from datetime import datetime, timezone
s = "2008-09-17 14:02:00"

# to datetime object:
dt = datetime.fromisoformat(s) # Python 3.7

# I'm on time zone Europe/Berlin; CEST/UTC+2 during summer 2008
dt = dt.astimezone()
print(dt)
# 2008-09-17 14:02:00+02:00

# ...and to UTC:
dtutc = dt.astimezone(timezone.utc)
print(dtutc)
# 2008-09-17 12:02:00+00:00

There is one caveat though, see astimezone(None) gives aware datetime, unaware of DST.

Answer 5

How about -

time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime(seconds))

if seconds is None then it converts the local time to UTC time else converts the passed in time to UTC.

Answer 6

You can do it with:

>>> from time import strftime, gmtime, localtime
>>> strftime('%H:%M:%S', gmtime()) #UTC time
>>> strftime('%H:%M:%S', localtime()) # localtime