Free Korean Age Calculator: Korean Age, International Age and Year Age
This Korean age calculator gives your age three ways. Type a birth year or a full date of birth and see your international age (만 나이), your Korean age (세는 나이) and your year age (연 나이), counted on today's date or any date you pick. It also shows how to say the age in Korean and counts the days to your next birthday. It's free, needs no signup and runs in your browser.
Type a date of birth to see the international age, the Korean age and the year age side by side.
How the Korean age calculator works
Type your date of birth as a year (1998), a year and month (1998-03) or a full date, written as 1998-03-15, 1998년 3월 15일 or March 15, 1998. The calculator counts on today's date unless you change it, so you can also work out how old someone was, or will be, on any given day.
You get three ages. International age, 만 나이 (man nai), counts whole years since birth and goes up on your birthday. Korean age, 세는 나이 (seneun nai), starts at 1 on the day you're born and goes up every January 1. Year age, 연 나이 (yeon nai), is this year minus your birth year. On October 27, 2026, someone born on March 15, 1998, is 28 in international age, 29 in Korean age and 28 in year age.
With only a birth year, the calculator can't tell whether your birthday has passed, so it shows international age as a range. Born in 1998, you're 27 or 28 in 2026. Korean age and year age don't depend on the birthday, so those two stay exact.
The calculator also shows how to say the age in Korean, in everyday speech and on forms, and counts the days to your next birthday. Everything runs in your browser.
만 나이, 세는 나이 and 연 나이: three ways to count age
International age is the one most of the world uses. You're 0 until your first birthday, and a year older on each birthday after that.
Korean age goes up for everyone at once, on January 1. A baby born on December 31 is 1 in Korean age that day and 2 the next day, January 1, while still 0 in international age. Everyone born in the same year has the same Korean age, all year.
Year age sits between the two. It goes up on January 1 like Korean age but starts at 0, so it's always one less than Korean age. From your birthday to December 31, it matches your international age.
February 29 only comes in leap years. In other years, someone born on February 29 turns a year older on March 1.
Which age to use in Korea
For anything official, use international age. Since June 28, 2023, amendments to the Civil Act and the General Act on Public Administration have made international age the standard in Korean law and administration, so Korea legally dropped Korean age that year. On a form, your age is your 만 나이.
A few rules still go by year age. Military service is one. Another is the age for buying alcohol and tobacco, which under the Youth Protection Act starts on January 1 of the year you turn 19, whatever the date of your birthday.
Korean age is still common in everyday conversation, which is why the calculator shows all three. When a Korean friend tells you their age, it may be a year or two more than their international age.
How to say your age in Korean
In everyday speech, age takes native Korean numbers and 살. 25 is 스물다섯 살 (seumuldaseot sal), and "I'm 25" is 스물다섯 살이에요. Some numbers shorten before 살: 한 살 for 1, 두 살 for 2, 세 살 for 3, 네 살 for 4 and 스무 살 for 20. To ask someone's age, say 몇 살이에요?
On forms, age takes Sino-Korean numbers and 세, with 만 in front for international age: 만 25세, read man isibose. That makes 세 살 and 3세 the same age, three, in speech and on paper.
Babies under 1 are counted in months, with 개월, so a six-month-old is 6개월.
The Korean number converter writes any number in native Korean up to 99 and in Sino-Korean, with the form used before a counter, so 21 comes out as 스물한, as in 스물한 살.
Frequently asked questions
Is this Korean age calculator free?
Yes. There's no account or email address, and everything runs in your browser.
What is my Korean age?
Take the current year, subtract your birth year and add 1. Born in 1998, you're 29 in Korean age in 2026, whatever your birthday. Everyone born in the same year shares a Korean age, and it goes up on January 1.
What is 만 나이?
만 나이 (man nai) is international age: the whole years since you were born, going up on your birthday. It's the age used in Korean law and administration, written on forms with 만 and 세, as in 만 25세.
Why does it show my age as "27 or 28"?
You typed only a birth year, so the calculator can't tell whether your birthday has passed yet this year, and your international age could be either. Type the full date and it gives one number.
How do I say my age in Korean?
In speech, use native Korean numbers and 살: 25 is 스물다섯 살 (seumuldaseot sal) and 20 is 스무 살. On forms, use Sino-Korean numbers and 세, as in 만 25세 (man isibose). A baby under 1 is counted in months, as in 6개월.
Which age should I put on a Korean form?
Use international age, 만 나이. It has been the standard in Korean law and administration since June 28, 2023. A few rules still use year age, among them the age for buying alcohol and tobacco, which starts on January 1 of the year you turn 19.
How old is a baby born on December 31?
The baby is 1 in Korean age that day and 2 the next day, January 1. In international age the baby is 0 until its first birthday, and in year age it's 1 from January 1.
What if I was born on February 29?
In a leap year, you turn a year older on February 29. In other years, the calculator counts you a year older on March 1.