Python - Compare two string dates in different formats

  • If both dates are datetime objects

    Comparison or Logical operators can be applied on 2 datetime objects as below.
    Results will be either True or False.

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    from datetime import datetime

dt1 = datetime(2020, 10, 15, 0, 0)
dt2 = datetime(2021, 12, 11, 0, 0)

print(dt1 == dt2)
print(dt1 < dt2)
print(dt1.year == dt2.year)

#Returns biggest number from each part
print(dt1 and dt2)
    Output:
      False
      True
      True
      2021-12-11 00:00:00

  • If both are string dates

    If dates are in string format, first convert to the datetime object before doing the comparison. Otherwise the dates will be treated as strings and we will not get the desired output.

    As seen in the below sample, both dates are same, but formatted differently. When we do a comparison directly without converting to datetime, result is False, even-though both dates are same. So, always convert string dates to datetime, before doing comparison.

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    from datetime import datetime

#Both dates are same. But formatted in different ways
sdt1 = '2020/10/15'
sdt2 = '10-15-2020'

dt1 = datetime.strptime(sdt1, '%Y/%m/%d')
dt2 = datetime.strptime(sdt2, '%m-%d-%Y')

#False, because string comparison is happening
print(sdt1 == sdt2)
#Returns True
print(dt1 == dt2)
    Output:
      False
      True
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