When I found out that Korean has not one but two entirely separate number systems, I genuinely thought someone was pranking me. Two? Why? Who decided this was necessary?
But here I am, months later, and learning how to count in Korean with both systems has actually become one of the more rewarding parts of studying the language. Once you understand the logic behind when to use which system, it clicks. I promise. Let me break it down the way I wish someone had explained it to me from the start.
The Two Korean Number Systems: Native Korean vs. Sino-Korean
Korean has two counting systems: Native Korean numbers (고유어 수사, goyueo susa) and Sino-Korean numbers (한자어 수사, hanjaeo susa). Sino-Korean numbers come from Chinese characters (hanja), while Native Korean numbers are original Korean words.
Both systems are used regularly in everyday Korean. You can’t just pick one and ignore the other — they’re used in different contexts, and mixing them up will confuse people. It’s like if English used Roman numerals for some things and regular numbers for others, and everyone just knew which was which.
The good news: once you learn the rules, the “which system” question becomes automatic. The bad news: you do need to memorize both sets. No shortcuts there.
Sino-Korean Numbers: 일, 이, 삼 (Il, I, Sam)
Sino-Korean numbers are the Chinese-origin numbers and they go like this:
1 = 일 (il)
2 = 이 (i)
3 = 삼 (sam)
4 = 사 (sa)
5 = 오 (o)
6 = 육 (yuk)
7 = 칠 (chil)
8 = 팔 (pal)
9 = 구 (gu)
10 = 십 (sip)
The beautiful thing about Sino-Korean numbers is that they’re incredibly logical for bigger numbers. 11 is 십일 (sip-il) — literally “ten-one.” 25 is 이십오 (i-sip-o) — “two-ten-five.” 100 is 백 (baek). 1,000 is 천 (cheon). You just stack them together like building blocks.
When to use Sino-Korean numbers:
• Dates: months, days, years. April is 사월 (sawol, “four-month”). The 15th is 십오일 (siboh-il).
• Money: 오천 원 (ocheon won) = 5,000 won.
• Phone numbers: read digit by digit using Sino-Korean.
• Addresses and floor numbers.
• Minutes when telling time (but not hours — that’s Native Korean, because Korean likes to keep us on our toes).
• Math and measurements.
Native Korean Numbers: 하나, 둘, 셋 (Hana, Dul, Set)
Native Korean numbers are the original Korean counting words:
1 = 하나 (hana)
2 = 둘 (dul)
3 = 셋 (set)
4 = 넷 (net)
5 = 다섯 (daseot)
6 = 여섯 (yeoseot)
7 = 일곱 (ilgop)
8 = 여덟 (yeodeol)
9 = 아홉 (ahop)
10 = 열 (yeol)
Native Korean numbers only go up to 99 in regular use (though technically they exist for higher numbers, Koreans switch to Sino-Korean above 99). For numbers 11-19, you say 열 (ten) + the unit: 열하나 (yeol-hana) = 11, 열둘 (yeol-dul) = 12. For 20, it’s 스물 (seumul), 30 is 서른 (seoreun), 40 is 마흔 (maheun), and so on.
Here’s a tricky detail: when Native Korean numbers 1-4 and 20 are used before a counter (more on those in a second), they change form. 하나 becomes 한, 둘 becomes 두, 셋 becomes 세, 넷 becomes 네, and 스물 becomes 스무. So “one person” isn’t 하나 명, it’s 한 명 (han myeong). This messed me up for weeks.
When to use Native Korean numbers:
• Counting objects with counters (two apples, three books, etc.).
• Hours when telling time. 3 o’clock = 세 시 (se si).
• Age in casual/everyday speech. “I’m 27” = 스물일곱 살 (seumul-ilgop sal).
• Counting people, animals, items in general.
Korean Counters: The Secret Third Thing Nobody Warned Me About
Just when you thought you had the two number systems figured out, Korean throws in counters (분류사, bunlyusa). These are special words that go after the number depending on what you’re counting. English has a few of these — “two sheets of paper,” “three heads of cattle” — but Korean has counters for practically everything.
Common counters you’ll use all the time:
• 개 (gae) — general counter for things/objects. This is your default when you don’t know the specific counter.
• 명 (myeong) — people (polite). 두 명 = two people.
• 마리 (mari) — animals. 세 마리 = three animals.
• 잔 (jan) — cups/glasses of drinks. 커피 한 잔 = one cup of coffee.
• 병 (byeong) — bottles. 물 두 병 = two bottles of water.
• 권 (gwon) — books. 책 세 권 = three books.
• 장 (jang) — flat things (paper, tickets). 종이 다섯 장 = five sheets of paper.
• 벌 (beol) — sets of clothing. 옷 한 벌 = one set of clothes.
Most counters use Native Korean numbers. So it’s 사과 두 개 (sagwa du gae) = two apples, using the Native Korean 둘/두. But a few counters use Sino-Korean numbers (like 분 for minutes and 층 for building floors). Yes, you just have to memorize which goes with which. Yes, it’s a lot. Yes, Koreans will understand you even if you get it wrong — they’ll just find it endearing.
Telling Time: Where Both Systems Collide
Telling time in Korean is where learning to count in Korean reaches its final boss level, because you use both systems in the same sentence. Hours use Native Korean numbers. Minutes use Sino-Korean numbers. Why? I have accepted that some questions don’t have satisfying answers.
3:25 = 세 시 이십오 분 (se si isibo bun)
세 (se) = three (Native Korean, shortened from 셋)
시 (si) = o’clock
이십오 (isibo) = twenty-five (Sino-Korean)
분 (bun) = minutes
It feels absurd at first. But after enough practice, your brain just switches between systems mid-sentence without thinking. Kind of like how you don’t think about switching between “first” (ordinal) and “one” (cardinal) in English — it just happens.
Tips That Actually Helped Me Learn Korean Numbers
If you’re just starting to learn how to count in Korean, here are the things that helped me the most:
Start with Sino-Korean. It’s more regular, the patterns are cleaner, and you’ll use it for dates, money, and phone numbers — things you encounter immediately. Native Korean numbers are important but can come second.
Practice with real things. Count your groceries in Korean. Look at prices and say them in Sino-Korean. Check the time and say it out loud with both systems. Language sticks better when it’s attached to real life, not flashcards.
Don’t panic about counters. 개 (gae), the general object counter, will get you through 90% of situations. Learn that one first, then pick up specific counters as you encounter them naturally.
Accept the weirdness. Two number systems feels excessive until you realize that English has its own inconsistencies (why do we say “twelve” instead of “two-teen”?). Every language has its thing. Korean’s thing is dual numbers. You’ll survive.
Learning to count in Korean was one of the first times studying this language made me genuinely laugh at how different it is from English. But it was also one of the first things that made me feel real progress when it finally clicked. If you’re in the confused stage right now, keep going — the “oh, I actually get this now” moment is coming. 화이팅!