Why does Korea have 3 different ages? Korea officially abolished the traditional counting-age system for legal purposes on June 28, 2023, switching to international age as the default. But the old system didn’t disappear — it’s still used socially and casually — and a third system, calendar year age, is still the one actually written into law for things like the drinking and smoking age. Most calculators online only show you 2 of these. This one shows all 3.
The 3 Ages, Explained
The one the rest of the world uses — you turn a year older on your actual birthday. As of June 28, 2023, this is Korea’s official legal standard for contracts, medical care, and all government administration. If a Korean tells you their real legal age, this is it.
The traditional “counting age”: you’re already 1 when you’re born, and everyone gets a year older together on January 1st, not on their birthday. No longer legally binding, but still how a lot of Koreans casually talk about their own age, and it’s the reason a December-born baby can “turn 2” after just a few days.
Current year minus birth year — no birthday adjustment, but no “+1 at birth” either. This is the one still actually written into Korean law for the Youth Protection Act: everyone born in the same calendar year becomes legal to drink and smoke on the same day, January 1st, regardless of their actual birthday.
Saying Your Age in Korean
Korean uses its own native number words for age, not the Sino-Korean numbers you’d use for counting money or dates.
| Age | Korean | Romanized | Age | Korean | Romanized |
|---|---|---|---|---|---|
| 1 | 한 살 | han sal | 6 | 여섯 살 | yeoseot sal |
| 2 | 두 살 | du sal | 7 | 일곱 살 | ilgop sal |
| 3 | 세 살 | se sal | 8 | 여덟 살 | yeodeol sal |
| 4 | 네 살 | ne sal | 9 | 아홉 살 | ahop sal |
| 5 | 다섯 살 | daseot sal | 10 | 열 살 | yeol sal |
Round decades get their own irregular words too: 스무 살 (seumu sal, 20), 서른 살 (seoreun sal, 30), 마흔 살 (maheun sal, 40) — after 20, most people switch to just saying the number + 살 (sal) rather than the old native form.
Korea’s legal drinking and smoking age is 19, based on Year Age — meaning it’s tied to your birth year, not your birthday. Someone born December 31st and someone born January 1st of the same year become legal on the exact same day: January 1st of the year they turn 19. It sounds confusing, but it’s actually simpler at the register — bars and stores just check your birth year, not your exact date.
Korean Age FAQ
Is “Korean age” still used at all?
Legally, no — international age replaced it for every official purpose on June 28, 2023. Socially, yes — a lot of Koreans, especially older generations, still think and talk in terms of the traditional counting age day-to-day, even though it has no legal weight anymore.
Why was a baby born in December suddenly “2 years old”?
Under the old traditional counting system, you’re 1 the moment you’re born, and everyone ages up together on the next January 1st — not on individual birthdays. So a baby born December 30th turns “2” just days later on January 1st, despite being 2 days old. This quirk is a big part of why Korea moved to international age.
How is my Korean age different from my international age?
Traditional Korean age is usually 1 or 2 years higher than international age — 1 year higher for most of the year, and 2 years higher if your birthday hasn’t happened yet this calendar year (since you already “aged up” on January 1st but haven’t hit your actual birthday).
Does Korean age affect the drinking age?
Indirectly — the drinking age uses a third system, Year Age (current year minus birth year), not the traditional counting age. Everyone born in the same calendar year becomes legal to drink on the same January 1st, regardless of their exact birthday.
Why do Koreans ask your age so quickly when you meet?
Korean has an age-based honorific system built into the language itself — how you speak to someone (formal vs. casual, whether you can call them by name) depends on whether they’re older or younger than you. Age isn’t small talk in Korea the way it might feel elsewhere; it’s genuinely load-bearing information for how a conversation is supposed to go.
What age does mandatory military service start in Korea?
Liability starts at 18, and able-bodied men are generally required to enlist by 28, serving roughly 18-21 months depending on the branch. This is a real reason BTS and other idols have paused their careers to serve. Worth noting: as of 2026, Korea has been raising the age caps used to catch draft evasion abroad — the exemption age is moving from 38 to 43, extending the service obligation window from 40 to 45 for some cases.
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