How age difference is calculated
The age difference between two people is calculated using the same Y:M:D borrowing method as a standard age calculation. We find the gap from the older person's birth date to the younger person's birth date — not from today's date.
Example
1
Person A born: March 15, 1985 (older). Person B born: July 22, 1990 (younger).
2
Days: 22 − 15 = 7 days. Months: 7 − 3 = 4 months. Years: 1990 − 1985 = 5 years.
3
Result: 5 years, 4 months, 7 days age difference. Person A is older.
FAQ
Mathematically, they're the same: the time between two people's birth dates. "Age gap" is more commonly used in relationship contexts, while "age difference" is a more neutral term used in clinical, legal, and general contexts. Both are calculated the same way.
The gap in birth dates never changes — but the expressed age difference in years can vary by ±1 depending on whether one person has had their birthday this year and the other hasn't. This calculator shows the fixed gap between birth dates, which is always constant.