How Korean numbers work
Korean has two sets of numbers. Which one you use depends on what you are counting.
- Sino-Korean numbers (일, 이, 삼…) come from Chinese. Use them for dates, money, minutes, phone numbers, floors and most measurements.
- Native Korean numbers (하나, 둘, 셋…) are used to count things and people with counters like 개, 명 and 마리, for hours on the clock, and for ages with 살.
Two more rules catch almost every learner:
- Before a counter, some native numbers get shorter. 하나, 둘, 셋, 넷 and 스물 become 한, 두, 세, 네 and 스무: 한 개 (one item), 세 마리 (three animals), 스무 살 (20 years old).
- Big numbers are grouped by 만 (10,000), not by thousands. 15,000 is 만 오천 (10,000 + 5,000), and 35,000,000 is 삼천오백만 (3,500 × 10,000).
| Number | Sino-Korean | Native Korean |
|---|---|---|
| 1 | 일 (il) | 하나 (hana) |
| 2 | 이 (i) | 둘 (dul) |
| 3 | 삼 (sam) | 셋 (set) |
| 4 | 사 (sa) | 넷 (net) |
| 5 | 오 (o) | 다섯 (daseot) |
| 6 | 육 (yuk) | 여섯 (yeoseot) |
| 7 | 칠 (chil) | 일곱 (ilgop) |
| 8 | 팔 (pal) | 여덟 (yeodeol) |
| 9 | 구 (gu) | 아홉 (ahop) |
| 10 | 십 (sip) | 열 (yeol) |
| 20 | 이십 (isip) | 스물 (seumul) |
Native tens: 열 (10), 스물 (20), 서른 (30), 마흔 (40), 쉰 (50), 예순 (60), 일흔 (70), 여든 (80), 아흔 (90).
Which numbers to use: a cheat sheet
| What you're saying | Numbers | Example |
|---|---|---|
| Things, people, animals (개, 명, 마리, 병, 잔, 권, 장) | Native | 커피 세 잔 (three coffees) |
| Age with 살 | Native | 스무 살 (20 years old). Formal 세 takes Sino: 이십 세 |
| Clock hours (시) | Native | 세 시 (3 o'clock) |
| Minutes and seconds (분, 초) | Sino | 세 시 삼십 분 (3:30) |
| Hours of time (시간) | Native | 두 시간 (two hours) |
| Years, months, days (년, 월, 일) | Sino | 시월 구 일 (October 9) |
| Money (원) | Sino, grouped by 만 | 만 오천 원 (15,000 won) |
| Phone numbers | Sino, one digit at a time | 공일공 (010) |
| Floors, servings, months of time (층, 인분, 개월) | Sino | 삼 층, 이 인분, 삼 개월 |
With larger counts you will also hear Sino-Korean numbers with 명 and 개: 삼십오 명 is as correct as 서른다섯 명 (35 people).
Mistakes English speakers make
- Skipping the short form. 셋 마리 → 세 마리, 스물 살 → 스무 살. Before a counter, use the short form.
- Using the wrong set. 삼 마리 → 세 마리 (animals take native numbers). 일곱 시 서른 분 → 일곱 시 삼십 분 (minutes take Sino-Korean numbers).
- Shortening the wrong part. 21 items is 스물한 개, not 스무한 개. 스무 is only for 20 itself.
- Grouping by thousands. 15,000원 is 만 오천 원, not 십오천 원. 1,500원 is 천오백 원, not 십오백 원 ("fifteen hundred").
- Reading years in pairs. 2026년 is 이천이십육 년, not 이십 이십육 년 ("twenty twenty-six").
- Regular June and October. June is 유월 and October is 시월, not 육월 and 십월. The days stay regular: 6월 6일 is 유월 육 일.
FAQ
When do I use native vs Sino-Korean numbers?
Native numbers for counting with counters (개, 명, 마리…), clock hours and ages with 살. Sino-Korean numbers for dates, money, minutes, phone numbers and most measurements. The cheat sheet above covers the common cases.
Why does 셋 become 세 before a counter?
Before a counter, 하나, 둘, 셋, 넷 and 스물 take a shorter form: 한, 두, 세, 네, 스무. In bigger numbers only the last part changes: 스물한 개 (21), 서른세 살 (33).
How do I say 3:30 in Korean?
세 시 삼십 분: a native number for the hour and a Sino-Korean number for the minutes. 세 시 반 (half past three) is also common.
How do I read 15,000 won?
만 오천 원. Korean counts in units of 만 (10,000), so 15,000 is one 만 plus 오천 (5,000). For 100,000,000, keep the 일: 일억 원.
Is 일만 원 wrong?
No. 만 원 is the everyday reading, and 일만 원 is also correct in more formal use.
Why are June and October different?
These two month names are written the way they are traditionally pronounced: 유월 (not 육월) and 시월 (not 십월). It only applies to the month names, so the 6th and the 10th are still 육 일 and 십 일.
How do I read a phone number?
Read each digit with Sino-Korean numbers. Zero is usually 공 (영 is also fine): 010-1234-5678 is 공일공 일이삼사 오육칠팔.