Korean Numbers: Native vs Sino-Korean and Counters

Two number systems, two jobs

Korean runs two parallel number systems. The native Korean numbers (하나, 둘, 셋) handle counting things, people and hours, and stating age in speech. The Sino-Korean numbers (일, 이, 삼), borrowed from Chinese centuries ago, handle money, dates, minutes, phone numbers, floors and anything read off a written figure.

You cannot pick a favorite and ignore the other; each owns its territory. The good news is that native numbers fade out in practice above the small range, since large quantities switch to Sino-Korean anyway.

Native numbers, 1 to 10

Only 1, 2, 3, 4 and 20 change shape before a counter: 한, 두, 세, 네 and 스무 (seu-mu). The tens continue 스물 (seu-mul, 20), 서른 (seo-reun, 30), 마흔 (ma-heun, 40), 쉰 (swin, 50). Combine naturally: 스물다섯 (seu-mul-da-seot) is 25.

Number	Native Korean	Form before a counter
1	하나 (hana)	한 (han)
2	둘 (dul)	두 (du)
3	셋 (set)	세 (se)
4	넷 (net)	네 (ne)
5	다섯 (daseot)	다섯
6	여섯 (yeoseot)	여섯
7	일곱 (ilgop)	일곱
8	여덟 (yeodeol)	여덟
9	아홉 (ahop)	아홉
10	열 (yeol)	열

Sino-Korean numbers and place values

Build any number by stacking: 삼십 (sam-sip) is 30, 이백 (i-baek) is 200, 오천 (o-cheon) is 5,000. The key structural difference from English: Korean groups large numbers by ten thousands, and 만 (10,000) is a basic unit. 50,000 won is 오만 원 (o-man won), literally 'five ten-thousands won'.

Number	Sino-Korean
1 to 5	일 (il), 이 (i), 삼 (sam), 사 (sa), 오 (o)
6 to 10	육 (yuk), 칠 (chil), 팔 (pal), 구 (gu), 십 (sip)
100	백 (baek)
1,000	천 (cheon)
10,000	만 (man)

이거 얼마예요?	How much is this? i-geo eol-ma-ye-yo, the essential shopping question
오천 원이에요.	It is 5,000 won. o-cheon wo-ni-e-yo, money always takes Sino-Korean numbers

Counters: how Korean counts things

Korean rarely says 'two coffees'. It says 'coffee two cup': noun, native number in its modified form, counter. The counter matches the type of thing being counted.

Counter	Used for	Example
개 (gae)	things in general	사과 세 개, three apples
명 (myeong)	people	학생 네 명, four students
분 (bun)	people, honorific	손님 두 분, two guests
마리 (mari)	animals	강아지 세 마리, three puppies
잔 (jan)	cups and glasses	커피 두 잔, two cups of coffee
병 (byeong)	bottles	물 한 병, one bottle of water
권 (gwon)	books	책 한 권, one book
살 (sal)	years of age	스물다섯 살, 25 years old
층 (cheung)	floors, Sino numbers	오 층, fifth floor

커피 두 잔 주세요.	Two coffees, please. keo-pi du jan ju-se-yo, noun + number + counter, then the verb
사과 세 개 샀어요.	I bought three apples. sa-gwa se gae sa-sseo-yo
학생이 네 명 있어요.	There are four students. hak-saeng-i ne myeong i-sseo-yo
오 층에 살아요.	I live on the fifth floor. o cheung-e sa-ra-yo, floors take Sino-Korean numbers

Age, time and dates

Age in speech uses native numbers with 살: 스물다섯 살이에요, 'I am 25'. Telling time mixes the systems in one phrase: hours take native numbers with 시, minutes take Sino-Korean with 분. So 3:30 is 세 시 삼십 분, native 세 next to Sino 삼십 in the same breath.

Dates are fully Sino-Korean: 월 for the month, 일 for the day. Two months change shape: June is 유월 (yu-wol) and October is 시월 (si-wol), dropping a final consonant for smoother sound.

저는 스물다섯 살이에요.	I am 25 years old. jeo-neun seu-mul-da-seot sa-ri-e-yo, age uses native numbers
지금 세 시 삼십 분이에요.	It is 3:30 now. ji-geum se si sam-sip bu-ni-e-yo, native hour, Sino minutes
시월 구 일은 한글날이에요.	October 9 is Hangul Day. si-wol gu i-reun han-geul-la-ri-e-yo, note the irregular 시월

Memorize the time formula as a chunk: native + 시, Sino + 분. Learners who reason it out from scratch every time stay slow for months. Chunk it once and the mixing never trips you again.

Pronunciation corner

Numbers are high-frequency words, so small pronunciation errors get repeated hundreds of times. Fix these now.

여덟 (yeodeol, 8)	[jʌ.dʌl]	yuh-duhl; the final ㅂ in the spelling stays silent here
십 (sip, 10)	[ɕip̚]	ㅅ before i sounds like sh: 'ship' with an unreleased final p
육 (yuk, 6)	[juk̚]	yook, cut short with the tongue in position for a final k
원 (won, currency)	[wʌn]	closer to 'wun' than to the English word 'won'

Practice drill

Fill each blank with the correct number word or counter phrase, or answer the question.

저는 ___ 살이에요. (30 years old)Show answer
서른age takes native numbers
커피 ___ 잔 주세요. (two)Show answer
두modified form of 둘 before a counter
강아지 ___ 마리 있어요. (three)Show answer
세modified form of 셋
Write 10,000 won in Korean.Show answer
만 원만 alone means 10,000; no 일 in front
Write 3:15 using 시 and 분.Show answer
세 시 십오 분native hour, Sino-Korean minutes
Which number system do dates use?Show answer
Sino-Korean월 for months, 일 for days
책 ___ 권 읽었어요. (one)Show answer
한modified form of 하나
What is the modified form of 스물 (20) before a counter?Show answer
스무스무 살, 20 years old

Frequently asked questions

Why does Korean have two number systems?

The native numbers are original Korean; the Sino-Korean set was borrowed from Chinese along with much vocabulary. Over centuries each settled into fixed roles, so today the split is conventional and you learn it by category: counting and age native, money and dates Sino-Korean.

How high do native numbers actually go in real use?

In everyday speech they are common up to 99, and quantities beyond that switch to Sino-Korean. In practice you will use native numbers most for counts under 20, hours and age.

How do Koreans say phone numbers?

Digit by digit in Sino-Korean, with 공 for zero. 010 is read gong-il-gong. The dash in a written number is often read as 에 (e).

Is Korean age different from international age?

South Korea standardized international age for legal and administrative purposes in 2023. In conversation, people state age with native numbers and 살, and you may still occasionally hear the older inclusive counting from habit, so do not be surprised by a one-year gap.