Age Difference Calculator
Age difference between two people
Enter two birth dates and the calculator returns the gap in years, months and days, the total in days and weeks, and each person's age today. Today is Sunday, October 4, 2026.
Why the gap in years changes
The gap in days between two birth dates never changes, but the gap in completed years depends on the time of year. If one person was born in March and the other in November, their ages differ by one year for part of the year and by a different number for the rest. The exact difference in years, months and days is measured from the earlier birth date to the later one.
Common uses
People compare siblings, spouses, classmates, cousins and historical figures. The days and weeks figures give an unambiguous answer.
Frequently asked questions
How do I calculate the age difference between two people?
Enter both birth dates.
Is the gap in days fixed?
Yes.
Why does the gap in years change?
Completed years depend on the time of year.
Does the order of the dates matter?
No, the older date is used first.
Does it count leap days?
Yes.
Can it show weeks?
Yes.
Can it show months?
Yes.
Does it show each person's age today?
Yes.