Convert python datetime to timestamp in milliseconds

How do I convert a human-readable time such as 20.12.2016 09:38:42,76 to a Unix timestamp in milliseconds?

In Python 3 this can be done in 2 steps:

1. Convert timestring to datetime object
2. Multiply the timestamp of the datetime object by 1000 to convert it to milliseconds.

For example like this:

from datetime import datetime

dt_obj = datetime.strptime('20.12.2016 09:38:42,76',
                           '%d.%m.%Y %H:%M:%S,%f')
millisec = dt_obj.timestamp() * 1000

print(millisec)

Output:

1482223122760.0

strptime accepts your timestring and a format string as input. The timestring (first argument) specifies what you actually want to convert to a datetime object. The format string (second argument) specifies the actual format of the string that you have passed.

Here is the explanation of the format specifiers from the official documentation:

• %d - Day of the month as a zero-padded decimal number.

• %m - Month as a zero-padded decimal number.

• %Y - Year with century as a decimal number

• %H - Hour (24-hour clock) as a zero-padded decimal number.

• %M - Minute as a zero-padded decimal number.

• %S - Second as a zero-padded decimal number.

• %f - Microsecond as a decimal number, zero-padded to 6 digits.

For those who search for an answer without parsing and losing milliseconds, given dt_obj is a datetime:

python3 only, elegant

int(dt_obj.timestamp() * 1000)

both python2 and python3 compatible:

import time

int(time.mktime(dt_obj.utctimetuple()) * 1000 + dt_obj.microsecond / 1000)

For Python2.7 - modifying MYGz's answer to not strip milliseconds:

from datetime import datetime

d = datetime.strptime("20.12.2016 09:38:42,76", "%d.%m.%Y %H:%M:%S,%f").strftime('%s.%f')
d_in_ms = int(float(d)*1000)
print(d_in_ms)

print(datetime.fromtimestamp(float(d)))

Output:

1482248322760
2016-12-20 09:38:42.760000

You need to parse your time format using strptime.

>>> import time
>>> from datetime import datetime
>>> ts, ms = '20.12.2016 09:38:42,76'.split(',')
>>> ts
'20.12.2016 09:38:42'
>>> ms
'76'
>>> dt = datetime.strptime(ts, '%d.%m.%Y %H:%M:%S')
>>> time.mktime(dt.timetuple())*1000 + int(ms)*10
1482223122760.0

For Python2.7

You can format it into seconds and then multiply by 1000 to convert to millisecond.

from datetime import datetime

d = datetime.strptime("20.12.2016 09:38:42,76", "%d.%m.%Y %H:%M:%S,%f").strftime('%s')
d_in_ms = int(d)*1000
print(d_in_ms)

print(datetime.fromtimestamp(float(d)))

Output:

1482206922000
2016-12-20 09:38:42

A lot of these answers don't preserve the milliseconds from the datetime. This works for me

def datetime_to_ms_epoch(dt):
    microseconds = time.mktime(dt.timetuple()) * 1000000 + dt.microsecond
    return int(round(microseconds / float(1000)))