Korean Age Explained: Why Koreans Were a Year or Two Older
What is Korean age? Learn how the traditional system counted age, what changed with the 2023 law, how to ask someone's age in Korean, and why age still matters.
By a native Korean teacher · · 3 min read
Korean age is the traditional way of counting age in Korea: you are 1 when you are born, and everyone gets a year older on January 1. That made Koreans one or two years "older" than their international age. Since June 28, 2023, Korean law uses international age by default, but the old habit is still common in conversation.
Word at a glance
한국 나이hanguk nai
- Literally
- Korean age
- In natural English
- the traditional way of counting age in Korea
How traditional Korean age works
Under the traditional system, a baby is 1 at birth, and everyone adds a year on New Year's Day instead of on their birthday. To find someone's Korean age, take the current year, subtract their birth year, and add 1.
This is why a baby born on December 31 would turn 2 the very next day under Korean age, while being only one day old.
- Korean age = current year − birth year + 1
- International age (만 나이, man nai) = years since your birth, going up on your birthday
- Before your birthday in a given year, Korean age is 2 more than international age; after it, 1 more
What changed in 2023
On June 28, 2023, a revised law took effect that made international age the standard in legal and administrative matters, with the goal of reducing confusion. News reports at the time described Koreans "getting younger overnight."
There are exceptions. The legal age for buying alcohol and tobacco and the timing of military service are still counted by calendar year, so those rules did not change with the new law.
How Koreans talk about age today
In daily life, many people still mention their Korean age out of habit, and others now give their international age. To avoid confusion, Koreans often just ask for your birth year instead. If you say your age, adding 만으로 (maneuro, "in international age") makes it clear.
몇 살이에요?
Myeot sarieyo?
How old are you?
나이가 어떻게 되세요?
Naiga eotteoke doeseyo?
May I ask how old you are? (polite)
몇 년생이에요?
Myeon nyeonsaengieyo?
What year were you born?
만으로 스물다섯이에요.
Maneuro seumuldaseosieyo.
I'm 25 in international age.
Why age matters so much in Korean
Age shapes how Koreans speak to each other. It decides who uses polite speech, who can switch to casual speech first, and which titles people use, such as 오빠 (oppa), 언니 (eonni), 형 (hyeong) and 누나 (nuna). That is why asking someone's age early in a conversation is normal in Korea and not considered rude.
People born in the same year are 동갑 (donggap), and finding out you are the same age often means you can drop formal speech and become friends faster.
우리 동갑이네!
Uri donggabine!
We're the same age!
Korean age in K-pop
Older fan sites and interviews often list idols' ages in Korean age, which is why the numbers sometimes don't match what you expect. When in doubt, look at the birth year, which never changes.
Questions people ask
How do I calculate my Korean age?+
Subtract your birth year from the current year and add 1. For example, someone born in 2000 is 27 in Korean age in 2026.
Does South Korea still use Korean age?+
Not in law. Since June 28, 2023, international age is the standard for legal and administrative purposes, but many people still use Korean age casually.
Is it rude to ask someone's age in Korea?+
No. It is a normal question, because age decides how people address each other.
What does man nai mean?+
만 나이 (man nai) means international age, the number of full years since your birth.