How to calculate days from birthdate in Python

Posted On April 3, 2023

Calculating the number of days between a birthdate and the current date is a common task in data analysis and programming. In Python, you can use the datetime module to perform this calculation. In this blog post, we’ll go over how to do this.

1. Using the datetime module:

The datetime module provides several classes and functions to work with dates and times in Python. To calculate the number of days between a birthdate and the current date, we can use the datetime class to create a datetime object for the birthdate, and then subtract it from the current date to get a timedelta object representing the difference in days. Here’s an example:

import datetime

birthdate = datetime.datetime(2000, 1, 1)
now = datetime.datetime.now()

days_since_birth = (now - birthdate).days
print("Days since birth:", days_since_birth)

In this example, the birthdate is January 1st, 2000, and the current date is obtained using the now() method from the datetime class. The difference between the two dates is calculated by subtracting the birthdate datetime object from the current date datetime object. The result is a timedelta object, and the days attribute of this object gives the number of days between the two dates.

2. Using the date class:

In some cases, you might only need to work with dates and not with times. In this case, you can use the date class from the datetime module instead of the datetime class. The date class only holds information about the date and not the time, and it provides a toordinal() method that returns the proleptic Gregorian ordinal of the date, which can be used to calculate the number of days between two dates. Here’s an example:

import datetime

birthdate = datetime.date(2000, 1, 1)
now = datetime.date.today()

days_since_birth = (now - birthdate).days
print("Days since birth:", days_since_birth)

In this example, we create a date object for the birthdate and the current date, and then subtract the birthdate date object from the current date date object to get a timedelta object representing the difference in days. The days attribute of this object gives the number of days between the two dates.

These are some of the ways you can calculate the number of days between a birthdate and the current date in Python using the datetime module. Depending on your needs, you can choose the method that works best for you.