Korean age · Free
One birthday,
three ages.
Korea counted age three ways until 2023, and two of them are still in daily use. Enter a birth date and see all three, with the rule behind each.
Why Koreans ask your birth year
Speech changes with age: whether someone is 형·누나·오빠·언니 or a 동생 decides the verb endings. Year age settles it in one question.
Since 2023 the answer to “how old are you?” is the international age, but the question at a first meeting is still “what year were you born?”.
The same birth date builds a Saju chart — the year pillar is the animal and colour of your year, the day pillar your Day Master.
Arithmetic on the calendar, the same for everybody. Sources: 법제처 (Ministry of Government Legislation), 만 나이 통일법 2023-06-28; school-entry rule of 2009 for the fast-birthday cutoff.