Korean Age Calculator
Enter a birth date to calculate international age (man-nai), year age, and counting age (Korean traditional age) all at once.
Frequently Asked Questions
How is international age (man-nai) calculated?
If your birthday has already passed this year: (current year − birth year). If it has not passed yet: subtract 1 from that result. You start at 0 at birth and gain one year on each subsequent birthday.
What is year age?
Year age is simply (current year − birth year), regardless of whether your birthday has passed. It is used as the age standard in certain Korean laws such as the Military Service Act and the Youth Protection Act.
What is counting age (Korean traditional age)?
In this traditional system, you are 1 year old at birth and gain one year every January 1st. It is calculated as (current year − birth year + 1). Since the international age unification on June 28, 2023, it is no longer a legal standard and is mainly used in everyday conversation.
Why do the three age types differ?
They use different reference points. International age uses your birthday; year age and counting age use the calendar year; and counting age treats the birth year itself as age 1. Depending on the method and where you are in the year relative to your birthday, the results can differ by up to two years.