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Date Time Format Unknown [duplicate]

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How to convert integer timestamp into a datetime
(3 answers)
Closed last year.
I am trying to figure out a time format used by someone else. In addition to the date, I have time with an example being the following:
1641859200000
I cant seem to figure out what time or date time format this is. It cannot be HHMMSS, because in this example the second is 85, which is not possible. Any idea what format this is, and how I can convert it using Python to HH:MM:SS ?
Thank you :)

You have a timestamp in seconds from Epoch since January 1, 1970 (midnight UTC/GMT). To convert to a datetime, use:
from datetime import datetime
print(datetime.fromtimestamp(1641859200000 / 1000))
# Output
2022-01-11 01:00:00
Note: you have to divide by 1000 because this timestamp contains milliseconds and Epoch should be in seconds.

This is a Unix-Timestamp.
You can convert in a human-readable format like this:
from datetime import datetime
timestamp = 1641859200000/1000
dt = datetime.fromtimestamp(timestamp)
print(dt)
Edit: didn't check the actual timestamp, whyever, this has to be divided by 1000 as done in the othe answer.

This probably is a unix timestamp https://en.wikipedia.org/wiki/Unix_time. The factor 1000 stems from a millisecond representation I think. Depends on, from where you got this stamp.
You can convert it using:
>>> datetime.datetime.fromtimestamp(1641859200000/1000)
datetime.datetime(2022, 1, 11, 1, 0)

Take a look at dateparser https://dateparser.readthedocs.io/.
It will help you figure out what the date and time is based on the range of input date strings:
pip install dateparser
>>> import dateparser
>>> dateparser.parse('1641859200000')
datetime.datetime(2022, 1, 11, 1, 0)
Your timestamp is miliseconds since Unix epoch in this case but if you ever run into similar problem dateparser could help you.
Regarding the second part of the question. Convertion to HH:MM:SS format
>> dt = datetime.datetime(2022, 1, 11, 1, 0)
>> dt.strftime("%H:%M:%S")
'01:00:00'
Additional info: Available Format Codes

Convert the unicode to datetime format

A function returns date and time in unicode format.
u'2014-03-06T04:38:51Z'
I wish to convert this to date and time format and subtract it with current datetime to get the number of days in between.
Thanks in advance

Check string is unicode
>>> import types
>>> type(u'2014-03-06T04:38:51Z') is types.UnicodeType
True
Converting strings to datetime:
>>> import datetime
>>> datetime.datetime.strptime(u'2014-03-06T04:38:51Z', '%Y-%m-%dT%H:%M:%SZ')
datetime.datetime(2014, 3, 6, 4, 38, 51)
Subtract from today to
>>> import datetime
>>> today = datetime.datetime.today()
>>> yourdate = datetime.datetime.strptime(u'2014-03-06T04:38:51Z', '%Y-%m-%dT%H:%M:%SZ')
>>> difference = today - yourdate
print str(difference)

First you have to convert your string to a datetime.datetime object.
import datetime
then = datetime.datetime.strptime(u'2014-03-06T04:38:51Z', "%Y-%m-%dT%H:%M:%SZ")
then represents itself as datetime.datetime(2014, 3, 6, 4, 38, 51), which looks about right. Then you have to get today's date as a datetime.datetime.
now = datetime.datetime.now()
Finally subtract it from your date (or vice versa - the question didn't make it clear).delta is a datetime.timedelta object that stores increments in days, seconds and microseconds. The latter two are always positive, the first can be negative.
for delta in (now-then, then-now):
print(delta, "::", delta.days, delta.seconds, delta.microseconds)
This prints out:
-1 day, 20:18:14.250142 :: -1 73094 250142
3:41:45.749858 :: 0 13305 749858
Best try it with a few examples to convince yourself it's correct.

Date Time Formats in Python

What are these date-time formats? I need to convert them to the same format, to check if they are the same. These are just two coming from a separate data source, so I need to find a way to make them the same format. Any ideas?
2013-07-12T07:00:00Z
2013-07-10T11:00:00.000Z
Thanks in advance

That extra .000 is micro seconds.
This will convert a date string of a format to datetime object.
import datetime
d1 = datetime.datetime.strptime("2013-07-12T07:00:00Z","%Y-%m-%dT%H:%M:%SZ")
d2 = datetime.datetime.strptime("2013-07-10T11:00:00.000Z","%Y-%m-%dT%H:%M:%S.%fZ")
Then convert them into any format depending on your requirement, by using:
new_format = "%Y-%m-%d"
d1.strftime(new_format)

perhaps use .isoformat()
string in ISO 8601 format, YYYY-MM-DDTHH:MM:SS[.mmmmmm][+HH:MM]
>>> import datetime
>>> datetime.datetime.utcnow().isoformat() + "Z"
'2013-07-11T22:26:51.564000Z'
>>>
Z specifies "zulu" time or UTC.
You can also add the timezone component by making your datetime object timezone aware by applying the appropriate tzinfo object. With the tzinfo applied the .isoformat() method will include the appropriate utc offset in the output:
>>> d = datetime.datetime.utcnow().replace(tzinfo=datetime.timezone.utc)
>>> d.isoformat()
'2019-11-11T00:52:43.349356+00:00'
You can remove the microseconds by change the microseconds value to 0:
>>> no_ms = d.replace(microsecond=0)
>>> no_ms.isoformat()
'2019-11-11T00:52:43+00:00'
Also, as of python 3.7 the .fromisoformat() method is available to load an iso formatted datetime string into a python datetime object:
>>> datetime.datetime.fromisoformat('2019-11-11T00:52:43+00:00')
datetime.datetime(2019, 11, 11, 0, 52, 43, tzinfo=datetime.timezone.utc)
http://www.ietf.org/rfc/rfc3339.txt

you can try to trim the string
data = "2019-10-22T00:00:00.000-05:00"
result1 = datetime.datetime.strptime(data[0:19],"%Y-%m-%dT%H:%M:%S")
result2 = datetime.datetime.strptime(data[0:23],"%Y-%m-%dT%H:%M:%S.%f")
result3 = datetime.datetime.strptime(data[0:9], "%Y-%m-%d")

use datetime module.
For a variable
import datetime
def convertDate(d):
new_date = datetime.datetime.strptime(d,"%Y-%m-%dT%H:%M:%S.%fZ")
return new_date.date()
convertDate("2019-12-23T00:00:00.000Z")
you can change the ".date()" to ".year", ".month", ".day" etc...
Output: # is now a datetime object
datetime.date(2019, 12, 23)
For a DataFrame column, use apply()
df['new_column'] = df['date_column'].apply(convertDate)

* Short and best way:
str(datetime.datetime.now()).replace(' ','T')
or
str(datetime.datetime.now()).replace(' ','T') + "Z"

Determine start and end time of current day (UTC -> EST -> UTC) ; Python

I am storing all my times in UTC and my system is set to UTC (though I am in EST).
I have dates stored as:
Wed, 20 Feb 2013 03:51:39 +0000
However, I would like to select information based off today for EST, so I am attempting to:
Get current time as UTC and change to EST
datetime.utcnow().replace(tzinfo=tz.tzutc()).astimezone(tz.gettz('America/New_York'))
2013-02-19 23:17:20.560898-05:00
Next I want to get the start time for the EST day (2013-02-19 00:00:00.000000-05:00) and the end time (2013-02-19 23:59:59.99999-05:00)
Once I have those values, I'd like to convert back to UTC, so I have a high and low value I can clamp by that's correct my EST (my timezone).
If this isn't the best way to do this, or I'm missing something (does seem overly complicated to me) please help me see the light!
TIA
Update per answer:
d1 = datetime.utcnow().replace(tzinfo=tz.tzutc()).astimezone(tz.gettz('America/New_York'))
print d1.strftime("%m %d %Y") ; d2 = d1.replace(day=d1.day + 1) ; print d2.strftime("%m %d %Y")
That will give me
02 20 2013
02 21 2013
Which is correct. I now need to generate the full EST time from that and then convert to UTC. This I cannot figure out. Actually, I probably want to convert to UTC epoch timestamp when complete because that will make my database operations pretty easy (<, >, ==, etc).

The first step of getting current time as UTC and converting it to EST seems a bit pointless. Do you use that time for anything?
Other than that it seems rather straighforward. You want to get the start and end of a day EST in UTC, so you create them and convert them to UTC. That's not so complicated. :-)
You might want to look at your matching routines though, so that you can use the start of today as the lower value, and the start of tomorrow as the higher, so you don't have to deal with that 23:59:59.9999 time.
Update:
From my original understanding of your question, this is what you want to do:
First you want to get the current date as it is in UTC (so at 11pm EST the 12st, you want the 22nd, as it is the 22nd in UTC then.
>>> from datetime import datetime
>>> today = datetime.utcnow().date()
>>> today
datetime.date(2013, 2, 21)
Secondly you want 00:00:00 of that day in UTC, as start for a search.
>>> from dateutil import tz
>>> start = datetime(today.year, today.month, today.day, tzinfo=tz.tzutc())
datetime.datetime(2013, 2, 21, 0, 0, tzinfo=tzutc())
Except that you want to know what that time is in New York:
>>> from dateutil import tz
>>> est = tz.gettz('America/New_York')
>>> start = start.astimezone(est)
>>> start
datetime.datetime(2013, 2, 20, 19, 0, tzinfo=tzfile('/usr/share/zoneinfo/America/New_York'))
And you also want tomorrow as the end:
>>> from datetime import timedelta
>>> end = start + timedelta(1)
>>> end
datetime.datetime(2013, 2, 21, 19, 0, tzinfo=tzfile('/usr/share/zoneinfo/America/New_York'))
Summary:
today = datetime.utcnow().date()
start = datetime(today.year, today.month, today.day, tzinfo=tz.tzutc()).astimezone(est)
end = start + timedelta(1)

use datetime pytz will solve your problem.
def get_start_and_end():
tz = pytz.timezone('Asia/Shanghai')
today = datetime.now(tz=tz)
start = today.replace(hour=0, minute=0, second=0, microsecond=0)
end = start + timedelta(1)
return start, end

The question is old but maybe this helps:
import datetime
end_of_today = datetime.datetime.combine(datetime.datetime.today(), datetime.time(23, 59, 59, 999999))

I would definitely give Delorean a look, to solve your problem would follow a few steps.
You first need to parse your string. Excellent use the Delorean parse method.
>>> from delorean import parse
>>> d = parse("Wed, 20 Feb 2013 03:51:39 +0000")
>>> d
Delorean(datetime=2013-02-20 03:51:39+00:00, timezone=UTC)
Once you have the datetime that you parsed in a Delorean object you simply convert to EST
>>> d = d.shift('US/Eastern')
>>> d
Delorean(datetime=2013-02-19 22:51:39-05:00, timezone=US/Eastern)
Albeit pointless. You never use it for anything in your question, but super easy with Delorean.
Then you get the time now in EST
from delorean import Delorean
>>> d1 = Delorean(timezone="US/Eastern")
>>> d1
Delorean(datetime=2013-02-21 00:35:56.405256-05:00, timezone=US/Eastern)
Now for the truncation step.
>>> d.truncate('day')
Delorean(datetime=2013-02-21 00:00:00-05:00, timezone=US/Eastern)
do the simple shift as above to UTC.
Now get the end of day.
d = d.next_day(1) # move to the next day
Then to shift back one second. Something that the library needs I will be updating this. Simply get the datetime from the Delorean example by asking for it with datetime attribute.
d.datetime - timedelta(seconds=1)
datetime.datetime(2013, 2, 21, 23, 59, 59, tzinfo=<DstTzInfo 'US/Eastern' EST-1 day, 19:00:00 STD>)
Goodluck, but this library should simply your dealing with datetime operations :)

This is only a partial answer, because the rest has been covered well. I struggled with this for a while, as some technologies have inclusive searches, and I don't want to include any data from the first microsecond of the next day.
My solution for finding the end of day time quickly and correctly is this:
reference_time.replace(hour=0, minute=0, second=0, microsecond=0) + timedelta(days=1,microseconds=-1)

How about this
import datetime
datetime.datetime.combine(datetime.date.today(), datetime.time(00, 00, 00))
datetime.datetime.combine(datetime.date.today(), datetime.time(23, 59, 59))

Just ran into this, here's the simplest option I found:
from delorean import Delorean
today_d = Delorean()
sod_dt = today_d.start_of_day
eod_dt = today_d.end_of_day
sod_d = Delorean(sod_dt)
eod_d = Delorean(eod_dt)
sod_e = sod_d.epoch
eod_e = eod_d.epoch
to confirm:
In [69]: eod_e - sod_e
Out[69]: 86399.99999904633
close enough for most people

Here's a nice solution if you already use Arrow.
import arrow
now = arrow.now('US/Eastern')
start = now.floor('day')
end = now.ceil('day')
# Use the "datetime" property to access the actual datetime
print(start.datetime)

With python3.8, we can use as follow:
from datetime import datetime, timedelta, time
from pytz import timezone
today = datetime.utcnow()
start_of_day = datetime.combine(today, time.min).astimezone(tz=timezone('America/New_York'))
end_of_day = datetime.combine(today, time.max).astimezone(tz=timezone('America/New_York'))

To get the min and max time of the day, you could use datetime.time that gives you the earliest and latest representalbe time:
time.min --> datetime.time(0, 0)
time.max --> datetime.time(23, 59, 59, 999999)
and then you can combine this with datetime.now() or the specific date you want as below to get the desired result
from datetime import datetime, time
tmp = datetime.combine(datetime.now(), time.max)
print(tmp) --> 2022-09-27 23:59:59.999999
from datetime import datetime, time
tmp = datetime.combine(datetime.now(), time.max)
print(tmp) --> 2022-09-27 00:00:00

Simplest solution for getting the start of a day, though it might produce a phantom microsecond in unlucky floating point imprecision cases:
import datetime as dt
d = dt.datetime.now()
d = d - dt.timedelta(seconds=d.timestamp() % dt.timedelta(days=1).total_seconds())

Convert to UTC Timestamp

# parses some string into that format.
datetime1 = datetime.strptime(somestring, "%Y-%m-%dT%H:%M:%S")
# gets the seconds from the above date.
timestamp1 = time.mktime(datetime1.timetuple())
# adds milliseconds to the above seconds.
timeInMillis = int(timestamp1) * 1000
How do I (at any point in that code) turn the date into UTC format? I've been ploughing through the API for what seems like a century and cannot find anything that I can get working. Can anyone help? It's currently turning it into Eastern time i believe (however I'm in GMT but want UTC).
EDIT: I gave the answer to the guy with the closest to what I finally found out.
datetime1 = datetime.strptime(somestring, someformat)
timeInSeconds = calendar.timegm(datetime1.utctimetuple())
timeInMillis = timeInSeconds * 1000
:)

datetime.utcfromtimestamp is probably what you're looking for:
>>> timestamp1 = time.mktime(datetime.now().timetuple())
>>> timestamp1
1256049553.0
>>> datetime.utcfromtimestamp(timestamp1)
datetime.datetime(2009, 10, 20, 14, 39, 13)

I think you can use the utcoffset() method:
utc_time = datetime1 - datetime1.utcoffset()
The docs give an example of this using the astimezone() method here.
Additionally, if you're going to be dealing with timezones, you might want to look into the PyTZ library which has lots of helpful tools for converting datetime's into various timezones (including between EST and UTC)
With PyTZ:
from datetime import datetime
import pytz
utc = pytz.utc
eastern = pytz.timezone('US/Eastern')
# Using datetime1 from the question
datetime1 = datetime.strptime(somestring, "%Y-%m-%dT%H:%M:%S")
# First, tell Python what timezone that string was in (you said Eastern)
eastern_time = eastern.localize(datetime1)
# Then convert it from Eastern to UTC
utc_time = eastern_time.astimezone(utc)

def getDateAndTime(seconds=None):
"""
Converts seconds since the Epoch to a time tuple expressing UTC.
When 'seconds' is not passed in, convert the current time instead.
:Parameters:
- `seconds`: time in seconds from the epoch.
:Return:
Time in UTC format.
"""
return time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime(seconds))`
This converts local time to UTC
time.mktime(time.localtime(calendar.timegm(utc_time)))
http://feihonghsu.blogspot.com/2008/02/converting-from-local-time-to-utc.html
If converting a struct_time to seconds-since-the-epoch is done using mktime, this
conversion is in local timezone. There's no way to tell it to use any specific timezone, not even just UTC. The standard 'time' package always assumes that a time is in your local timezone.

You probably want one of these two:
import time
import datetime
from email.Utils import formatdate
rightnow = time.time()
utc = datetime.datetime.utcfromtimestamp(rightnow)
print utc
print formatdate(rightnow)
The two outputs look like this
2009-10-20 14:46:52.725000
Tue, 20 Oct 2009 14:46:52 -0000