Age Difference Calculator
Find the exact age gap between two people.
How this is calculated
The age gap is the exact calendar difference between the two birth dates — the same math as figuring out how old one person was, in years, months and days, on the day the other was born.
Sibling, couple, and generational age gaps
This is the calculator for comparing two people's ages rather than finding one person's exact age — common for working out a sibling age gap, a couple's age difference, or the span between generations in a family. Enter both birth dates and it returns the exact gap in years, months, and days, regardless of which date you enter first.
Frequently asked questions
Does the order I enter the two dates in matter?
No — the calculator works out which date is earlier automatically and always returns a positive age gap.
Can I see the age difference in months only, instead of years and months?
The result is broken down into years, months, and days together, which covers a months-only comparison naturally for gaps under a year.
Is this the same as the regular Age Calculator?
No — the Age Calculator finds one person's exact age as of today; this tool compares two people's ages against each other.