Calculators
Age Calculator
Enter a date of birth to find the exact age in years, months and days, the total number of months and days lived, and the number of days until the next birthday.
About the Age Calculator
Enter a date of birth and a reference date (defaults to today) to see the exact age in years, months and days, plus the total number of months and days lived. The "next birthday" tile only appears when the reference date is today.
How age is calculated
Age calculation uses calendar arithmetic: subtract the birth year from the reference year, then adjust by −1 if the birth month/day hasn't yet occurred in the reference year. This matches how birthdays are counted in everyday use.
The total days count uses the actual number of days between both dates, so it accounts for leap years correctly.
Frequently asked questions
How does the age calculator work?
It subtracts the birth year from the reference year, then adjusts by −1 if the birth month and day haven't yet occurred in the reference year. This matches how ages are counted in everyday use.
Can I calculate the age between any two dates?
Yes — change the "age at date" field to any date, not just today. The calculator will show the exact age between the two dates.