Korean Age Calculator

Three ways to count age in Korea

For a long time Korea used three different ages at once, which confused visitors and Koreans alike. Here is what each one means.

• International age (만 나이, man nai): you are 0 at birth and get a year older on your birthday. This is the official age since June 28, 2023.
• Old Korean age (세는 나이, seneun nai): you are 1 at birth, and everyone gets a year older together on January 1. A baby born on December 31 is “2” the next day.
• Year age (연 나이, yeon nai): the current year minus your birth year. It changes on January 1 for everyone, but starts from 0.

The 2023 change

On June 28, 2023, new rules made international age the standard for laws, contracts, documents and public services. If a document says 만 20세 or just 20세, it now means international age. The old Korean age was never a legal age, but it was everywhere in daily life, and many people still use it out of habit. To be clear, ask 만으로 몇 살이에요? (maneuro myeot 살이에요?).

Where year age still matters

Two important laws still use year age. Military service is based on the year you were born. And under the Youth Protection Act, you can buy alcohol and tobacco from January 1 of the year you turn 19, even before your 19th birthday. School classes are also grouped by birth year, January to December, which is why Koreans often ask what year you were born to work out who is older.

How to say your age in Korean

In conversation, use native Korean numbers with 살: 25 years old is 스물다섯 살 (seumuldaseot sal). Formal writing and the news use Sino-Korean numbers with 세: 이십오 세 (isibo se). To ask someone's age, say 몇 살이에요? (myeot 살이에요?). For older people, use the polite 연세가 어떻게 되세요? (yeonsega eotteoke 되세요?). The Korean Number Converter shows how to read any number.

Why age matters so much in Korea

Age decides how people talk to each other. Someone even one year older is addressed with more respect, and friends call each other by family-style titles such as 형 (hyeong), 오빠 (oppa), 누나 (nuna) and 언니 (eonni). People born in the same year are 동갑 (donggap) and can speak casually more easily. That is why “How old are you?” is one of the first questions Koreans ask.

Your zodiac animal (띠)

Each birth year has one of 12 animals, and Koreans often mention it: “I'm a dragon” is 저는 용띠예요 (jeoneun yongttiyeyo). Every year also has a name from the 60-year cycle, such as 병오년 for 2026, the year of the red horse. Fortune-tellers and traditional calendars change the animal at the Lunar New Year, not on January 1.