Everything About Korean Age Calculation
Three age systems have coexisted in Korea: international age counted from birthdays, traditional Korean age that starts at 1 and increases every New Year, and year age (current year minus birth year). Enter your birth date and this tool shows all three at once and explains why they differ.
Since the Age Unification Act took effect on June 28, 2023, age in Korean laws, contracts, and official documents is interpreted as international age unless otherwise specified. For people born in December, Korean age and international age can differ by up to two years, so knowing your exact international age matters for insurance, retirement, and pensions.
Not every age was unified, however. The Military Service Act, the Youth Protection Act (legal age for alcohol and tobacco), and the Elementary and Secondary Education Act (school entry) still use year age for administrative simplicity. That is why this calculator shows year age alongside the other two.
Pro tip: beyond your age, you can check the D-day until your next birthday, the total number of days you have lived, and the weekday you were born on. Celebrating your 10,000th or 20,000th day alive is a popular milestone. For countdowns to any other date, try the D-day calculator together with this tool.