Date of Birth Calculator

Date of Birth Calculator is a tool designed to determine your age, the day of the week you were born, and other important date-related information based on your date of birth.

What is the purpose of the Date of Birth Calculator?

The Date of Birth Calculator helps users calculate their age, identify the day of the week they were born, and perform other date-related calculations using their birth date.

Date of Birth Calculator formula

Here is the method used to calculate your age based on your date of birth:

Age = Current Date - Date of Birth

To calculate the day of the week:

• Day of the Week = A special algorithm called Zeller’s Congruence is used to determine the day of the week for a given date.

Note: To calculate your age, subtract your birth year from the current year. For more accurate results, consider the exact month and day.

Date of Birth Calculator examples

Example 1: Age calculation

1. Your date of birth: July 15, 1990.
2. Current date: January 6, 2025.
3. Follow these steps to calculate your age:
   Age = Current Date - Date of Birth
Age = 2025 - 1990 = 35 years old
   Result: This person is currently 35 years old.

Example 2: Day of the week calculation

1. Your date of birth: December 25, 2000.
2. Use Zeller’s Congruence formula to calculate the day of the week.
   Formula:
   h = (q + ((13 × (m + 1)) / 5) + K + (K / 4) + (J / 4) - 2 × J) % 7
q = day of the month (25)
m = month number (12 for December)
K = year of the century (last two digits of year)
J = century (first two digits of year)
h = 6 (Saturday)
   Result: December 25, 2000, was a Monday.

The Date of Birth Calculator is an essential tool for determining your age and the day of the week you were born based on your date of birth.