Enter the ages of the first and second person into the calculator to determine the age difference. This calculator can also evaluate any of the variables given the others are known.

Age Difference Formula

The following formula is used to calculate the age difference between two people.

AD = |A1 - A2|


  • AD is the age difference (years)
  • A1 is the age of the first person (years)
  • A2 is the age of the second person (years)

To calculate the age difference, subtract the age of the second person from the age of the first person. The absolute value of the result is the age difference. This ensures that the age difference is always a positive number, regardless of whether the first person is older or younger than the second person.

What is an Age Difference?

Age difference refers to the number of years that separate two people. This term is often used in the context of relationships to denote the gap in age between two partners. However, it can also be used in various other contexts such as the difference in age between siblings, colleagues, or friends. The significance or impact of an age difference can vary greatly depending on cultural, societal, and personal beliefs or norms.

How to Calculate Age Difference?

The following steps outline how to calculate the Age Difference using the formula: AD = |A1 – A2|.

  1. First, determine the age of the first person (A1) in years.
  2. Next, determine the age of the second person (A2) in years.
  3. Next, use the formula AD = |A1 – A2| to calculate the age difference.
  4. Finally, calculate the absolute value of the difference to get the age difference (AD).
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem:

Use the following variables as an example problem to test your knowledge.

age of the first person (A1) = 25 years

age of the second person (A2) = 30 years