Ages by birth year
Since 28 June 2023 Korean laws and official papers use 만 나이 unless a law says otherwise. Your birth date is saved only in this browser.
About the Korean age calculator
In Korea one person can have three different ages. Someone born in December can be 25, 26 and 27 years old on the same day, depending on how you count.
This calculator shows all three from your date of birth:
- 만 나이 (man nai) — the international age. You are 0 at birth and get one year older on each birthday. This is the legal age in Korea since 28 June 2023
- 세는 나이 (seneun nai) — the Korean counting age. You are 1 at birth, and everyone gets one year older on 1 January. This was the everyday age for a long time
- 연 나이 (yeon nai) — the year age. This year minus the birth year. Some laws still use it
You can also see the ages on any other date, and a table by birth year.
Features
- Three ages at once — 만 나이, 세는 나이 and 연 나이 side by side
- Any date — see your age today, on 1 January, or on the day of an exam, a trip or a contract
- Exact age — years, months and days, and months and days for babies under 2 (개월 수)
- Next changes — the date of your next birthday and of the next 1 January, and the new ages then
- Table by birth year — all three ages for each birth year, with the age before and after the birthday
- Saved for next time — your birth date stays in this browser only
How the three ages work
Take someone born on 25 December 2000, on 11 November 2026:
| Age | How to count | Result |
|---|---|---|
| 만 나이 (international) | 2026 − 2000 = 26, birthday not yet this year, so − 1 | 25 |
| 연 나이 (year age) | 2026 − 2000 | 26 |
| 세는 나이 (counting age) | 2026 − 2000 + 1 | 27 |
The famous case is a baby born on 31 December. On 1 January, one day later, the baby's counting age is already 2. Its international age is still 0.
What changed in June 2023
On 28 June 2023, Korea changed two laws, one of them the Civil Act. Since then, ages in laws, contracts and official papers mean 만 나이 (international age), unless a law clearly says something else. The government also asks people to use 만 나이 in everyday life.
Some rules still count by the year of birth (연 나이). Everyone born in the same year moves together:
- Military service — the year you turn 19 decides when you are called for the service check
- Alcohol and tobacco — under the Youth Protection Act you may buy them from 1 January of the year you turn 19, not from your birthday
- School — children start primary school in the March after the year they turn 6, so all children born in the same year start together
Rules can change. For something official, check with the office that asks for your age.
Ages by birth year (in 2026)
| Born in | 만 나이 before the birthday | 만 나이 from the birthday | 연 나이 | 세는 나이 |
|---|---|---|---|---|
| 2026 | – | 0 | 0 | 1 |
| 2020 | 5 | 6 | 6 | 7 |
| 2007 | 18 | 19 | 19 | 20 |
| 2000 | 25 | 26 | 26 | 27 |
| 1995 | 30 | 31 | 31 | 32 |
| 1990 | 35 | 36 | 36 | 37 |
| 1980 | 45 | 46 | 46 | 47 |
| 1970 | 55 | 56 | 56 | 57 |
The table in the tool shows every year, and it follows the date you pick.
How to use it
- Pick your date of birth
- Leave Age on this date as today, or pick another day
- Read your 만 나이, 세는 나이 and 연 나이
- See your exact age and the next dates when your ages change
- Look at the table for other birth years, or press Show all 100 years
Frequently asked questions
How old am I in Korean age?
For the old Korean counting age (세는 나이), take this year, subtract your birth year, and add 1. Born in 2000? In 2026 you are 27. But since June 2023 the official age is your international age (만 나이), the same as in most countries.
What is 만 나이?
만 나이 is your age counted from your birth date. You are 0 at birth and get one year older on your birthday. It is the age used in most of the world, and it is the legal age in Korea.
Do Koreans still use the counting age?
Less and less. Laws and official papers use 만 나이, and the government asks everyone to use it. Some people, mostly older people, still say their counting age in daily talk. If you are not sure, ask "만으로 몇 살이에요?" (how old are you in international age?).
Why do some rules still use 연 나이?
For military service, the alcohol and tobacco age, and school entry, everyone born in the same year is treated as one group. That is simpler for these systems, so they kept counting by the year of birth.
When can I drink alcohol in Korea?
Under the Youth Protection Act you may buy alcohol and tobacco from 1 January of the year you turn 19. Born in 2007? From 1 January 2026. This is a year rule, so your birthday does not matter.
What if I was born on 29 February?
In a year without 29 February, this tool moves your birthday to 1 March. Your 만 나이 goes up on that day.
Why does my counting age go up on 1 January?
In the counting age, everyone gets one year older together at the new year. The calendar year is what counts, not your birthday. In old times people often counted it at the Lunar New Year (설날), but in recent decades 1 January was used.
Good to know
- All ages use the dates on the calendar, not the time of birth
- Your birth date is saved only in this browser, so it is there next time
- Nothing you type is sent anywhere
- For an official age, check the rule of the office that asks
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- Korean Keyboard — type in Hangul online
- D-Day Calculator — 100 days, 1000 days and D-day counting
- Japanese Era Converter — Reiwa, Heisei and Showa years
