Korean age explained — 만 나이 (man nai) and the 2023 law

Why did my Korean friend say I'm 27, when I'm only 25?

Let's follow one person. You were born in March 2000. It is January 10, 2026. You say, "I'm 25." Your friend smiles and says, "Then you're 26." Another friend says, "No, you're 27." Nobody is making a mistake. Korea has used three ways to count age, and each friend used a different one.

Three friends, three answers

Here is what each friend did.

So your Korean age is one or two years higher than your full age. It depends on whether your birthday has passed this year.

The old Korean age counted the year you were born as your first year. Then everyone in Korea "grew older" together on New Year's Day.

Since June 28, 2023, Korean law and government papers use 만 나이 (man nai). This is your international age. The old "Korean age" is something you may still hear in daily life.

The day everyone became younger

In December 2022, Korea changed two laws. One is 행정기본법 (Haengjeong Gibonbeop), the basic law for government work. The other is 민법 (Minbeop), the Civil Act. People call this the "만 나이 통일법" (man nai tongilbeop, "unified age law").

It started on June 28, 2023. Here is the main rule:

• In law and in government work, your age is your full age.
• This is true unless a law has its own special rule.
• Contracts and public papers also use full age.

Why? Different ways of counting age caused confusion in society and in government. They also caused legal fights. The government wanted one clear age to reduce these problems.

On June 28, 2023, many Koreans felt one or two years "younger" overnight. The Civil Act had already used full age since 1962. What changed is that full age became the clear rule in government work and in most laws, and people were asked to use it in daily life too.

Where the old "year age" still lives

The law has exceptions. In these cases, Korea still uses 연 나이 (this year minus your birth year).

1. Military service. The Military Service Act uses year age. Young men get their military check in the year they turn 19 in year age.
2. Buying alcohol and cigarettes. The Juvenile Protection Act uses year age. You can buy them from January 1 of the year you turn 19.
3. Civil service exams. Some public job exams still count by year.

So a Korean friend born in December can buy a beer on January 1. They might still be only 18 in full age.

School has its own rule, and it is not a year-age rule. A child turns six (in full age) during one year, then starts elementary school on March 1 of the next year. That is why all children born in the same year start school together.

What your friends will ask you

Back to your new friends. In daily life, people still ask about age often. Here are the questions you will hear.

The last question is very useful. Your birth year gives a clear answer, and nobody needs to do math. You can answer like this: 2000년생이에요 (icheon nyeonsaengieyo, "I was born in 2000").

If you want to give your full age, add 만: 만 스물다섯 살이에요 (man seumuldaseot sarieyo, "I am 25 in full age").

A word you may hear: 빠른

Someone may say 빠른 2000 (ppareun icheon, "early 2000"). 빠른 means "fast" or "early."

In the past, the cutoff date for starting school was March 1, not January 1. So children born in January or February could start school with children born the year before. People call them "빠른" plus their birth year.

The rule changed. Since 2010, children born in the same calendar year start school together. So the 빠른 situation is mostly about adults today.

Why they ask at all

It can feel strange to be asked your age at a first meeting. But in Korea, it is often a practical question.

Age often helps people choose:

• How to speak. Korean has polite and casual speech levels. You can read more in our guide to Korean polite speech.
• What to call each other. Words like 형 (hyeong), 오빠 (oppa), 언니 (eonni) and 누나 (nuna) depend on who is older. Our guide to these four words explains them.

People born in the same year often call each other 동갑 (donggap, "the same age"). Being 동갑 can make it easier to become friends.

For many Koreans, asking your age is a way to know how to treat you, not a rude question. Still, you can answer with a smile and say your birth year.