Age Gap Calculator
Enter two birth dates to calculate the exact age gap between them — in years, months, and days — and see who's older.
Age gap
—
Enter both birth dates to calculate.
How the Age Gap formula works
The same calendar-difference method used for single-person age calculations, applied between two birth dates instead of one birth date and today:
years, months, days = calendar difference between the two birth dates, borrowing across months/years as needed
Step-by-step calculation
- Identify which of the two birth dates is earlier.
- Subtract the earlier date from the later date, component by component (years, months, days), borrowing from the previous month or year as needed.
- The result is the exact age gap between the two people.
Worked example
Person A born March 10, 1990 and Person B born July 22, 1993: the age gap is 3 years, 4 months, 12 days, with Person A being the older of the two.
Frequently asked questions
Does the age gap change over time?
No — the age gap in years, months, and days between two specific birth dates is fixed forever, even though both people's ages keep increasing together.
Can this handle either birth date being entered first?
Yes — enter the two dates in any order; the calculator automatically determines which is earlier and reports the gap along with who's older.