Python: Calculate number of days between two datetimes

Last update on April 22 2025 12:49:05 (UTC/GMT +8 hours)

33. Days Between DateTimes

Write a Python program to calculate the number of days between two date times.

Sample Solution:

Python Code:

# Import the datetime module
import datetime
# Import the datetime class from datetime module
from datetime import datetime

# Define a function called differ_days which calculates the difference in days between two datetime objects
def differ_days(date1, date2):
    # Assign date1 to variable a
    a = date1
    # Assign date2 to variable b
    b = date2
    # Return the difference in days between the two datetime objects
    return (a - b).days

# Print an empty line
print()
# Print the difference in days between October 12, 2016 (midnight) and December 10, 2015 (midnight)
print(differ_days((datetime(2016, 10, 12, 0, 0, 0)), datetime(2015, 12, 10, 0, 0, 0)))
# Print the difference in days between October 12, 2016 (midnight) and December 10, 2015 (11:59:59 PM)
print(differ_days((datetime(2016, 10, 12, 0, 0, 0)), datetime(2015, 12, 10, 23, 59, 59)))
# Print an empty line
print()

Output:

307                                                                                                           
306

Explanation:

In the exercise above,

It imports the "datetime" module.
It defines a function named "differ_days()" that takes two datetime objects (date1 and date2) as input and returns the difference in days between them.
Inside the function:

It assigns the input datetime objects 'date1' and 'date2' to variables 'a' and 'b' respectively.
It calculates the difference in days between the two datetime objects using the 'days' attribute of the "timedelta" object obtained by subtracting 'b' from 'a'.
It returns the difference in days.

Then, it calls the differ_days function twice:

First, it calculates and prints the difference in days between October 12, 2016 (midnight) and December 10, 2015 (midnight).
Second, it calculates and prints the difference in days between October 12, 2016 (midnight) and December 10, 2015 (11:59:59 PM).

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to compute the difference in days between two datetime values including hours, minutes, and seconds.
Write a Python script to calculate the number of complete days between two datetime objects and then display the remainder hours.
Write a Python function to determine the total number of days between two date-time strings and also return the difference in seconds.
Write a Python program to find the gap between two datetime values and then output both the total days and the residual time in HH:MM:SS format.

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