Age Calculator
Calculate the exact age between two dates, down to the year, month, and day.
Pick a date of birth to see the exact age.
Internationally, age is counted using the "birthday" method: you turn a year older on your birthday and stay that age until the next one arrives. This calculator follows that convention, adjusting for varying month lengths and leap years so the day count is always exact.
East Asian cultures historically used "counted age," where a baby is one year old at birth and everyone gains a year at Lunar New Year rather than on their own birthday. South Korea legally abolished this system in June 2023, switching all official documents to the international method used here.
Common uses
- Filling out a visa, passport, or insurance application that asks for age calculated precisely to the day, rather than a rounded number of years.
- Working out exactly how many years, months, and days remain until a planned retirement date or a milestone birthday.
Frequently asked questions
- How is age calculated in Korea now?
- Since June 2023, South Korea uses the international "birthday" system for all legal and administrative purposes, the same method this calculator applies, replacing the older counted-age tradition.
- Why does the day count change around February 29?
- Leap years add an extra day to February, so a birthday that spans a leap year accumulates one more day of age than the same span in a non-leap year.
- Can I calculate the age between any two dates, not just today?
- Yes—set the second date field to any date, past or future, and the calculator will show the exact duration between it and the birth date.