Korean age is a way that Koreans calculate their age. It is always one or two years more than your international age. Koreans consider a year in the womb as counting towards their age, so everyone is one year old at birth. Everyone gets one year added to their Korean age on New Year’s Day.

Your Korean age will change on New Year’s Day, not on your birthday. People in Korea still celebrate their birthday’s on the day that they were born. However, it doesn’t affect their Korean age. Their Korean age changes on January 1st.

For example, if you were born on April 1st, then you would still celebrate your birthday on April 1st. However, your Korean age wouldn’t change until January 1st. Korean age isn’t calculated based on your birthday.

https://www.90daykorean.com/korean-age-all-about-age-in-korea/

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