Python – Get Yesterday’s date as a string in YYYY-MM-DD format

You Just need to subtract one day from today’s date. In Python datetime.timedelta object lets you create specific spans of time as a timedelta object.

datetime.timedelta(1) gives you the duration of “one day” and is subtractable from a datetime object. After you subtracted the objects you can use datetime.strftime in order to convert the result –which is a date object– to string format based on your format of choice:

>>> from datetime import datetime, timedelta
>>> yesterday = datetime.now() - timedelta(1)

>>> type(yesterday)                                                                                                                                                                                    
>>> datetime.datetime    

>>> datetime.strftime(yesterday, '%Y-%m-%d')
'2015-05-26'

Note that instead of calling the datetime.strftime function, you can also directly use strftime method of datetime objects:

>>> (datetime.now() - timedelta(1)).strftime('%Y-%m-%d')
'2015-05-26'

As a function:

from datetime import datetime, timedelta


def yesterday(frmt="%Y-%m-%d", string=True):
    yesterday = datetime.now() - timedelta(1)
    if string:
        return yesterday.strftime(frmt)
    return yesterday

example:

In [10]: yesterday()
Out[10]: '2022-05-13'

In [11]: yesterday(string=False)
Out[11]: datetime.datetime(2022, 5, 13, 12, 34, 31, 701270)