The formula to calculate age depends on the current date and the date of birth of an individual. Here’s a general formula to calculate age in years:

Age = Current Year – Birth Year

However, this formula assumes that the current year has already passed the birth year. To account for cases where the current year hasn’t passed the birth year yet, you can use the following formula:

Age = Current Year – Birth Year – 1

This formula deducts 1 from the result obtained by subtracting the birth year from the current year.

To calculate someone’s age, you need to know their date of birth and the current date. Subtracting the date of birth from the current date will give you the person’s age. Here’s an example:

Let’s say the date of birth is January 1, 1990, and the current date is July 7, 2023.

1. Calculate the number of years:
Current year – Birth year = 2023 – 1990 = 33 years

2. Check if the current month and day have passed the birth month and day. If the birth month and day have not been reached yet, subtract 1 from the calculated age. In this case, since the birth month is January and the current month is July, we don’t need to subtract.

So, based on the given information, the calculated age is 33 years.

Please note that this is a general method to calculate someone’s age, and it assumes the use of the Gregorian calendar. Different calendar systems or specific circumstances may require alternative calculations.