Korea now uses international age
Since June 28, 2023, ages in Korean laws, contracts and official documents use international age (만 나이, man nai) unless a law says otherwise (Framework Act on Public Administration, Art. 7-2; Civil Act, Art. 158). You start at 0 and add a year on each birthday.
Three ways Koreans count age
- International age (만 나이): add a year on your birthday. This is the official standard.
- Year age (연 나이): this year minus your birth year. It changes on January 1, not on your birthday.
- Traditional Korean age (세는 나이): you are 1 at birth and add a year every January 1 (year age + 1). You may still hear it in everyday talk.
Where year age still applies
- Buying alcohol and tobacco: the Juvenile Protection Act treats people under 19 as minors, but excludes anyone who has reached January 1 of the year they turn 19. In practice that is year age 19.
- Some laws, such as rules on military service age, set their own year-age standard.
- The usual elementary-school entry date is March 1 of the year after a child turns 6. Entry one year earlier or later is also allowed; check the application procedure with the school or education office (Elementary and Secondary Education Act, Art. 13).
Rules differ by law, so check the specific law for important decisions.
FAQ
What if I was born on February 29?
In non-leap years this tool uses March 1 for the age increase and next-birthday display. This is the tool’s calculation convention, not a guarantee of the legal rule in every country or program. Check the relevant authority for eligibility or contracts.
Is “Korean age” still used?
Officially, Korea uses international age. Traditional Korean age only shows up in casual conversation and has no legal effect.
Can I change the “as of” date?
Yes. Change it to see the age and next birthday on any date.
Sources
- Framework Act on Public Administration
- Civil Act
- Juvenile Protection Act
- Elementary and Secondary Education Act