Two number systems
| 1 | 2 | 3 | 4 | 5 | 10 | 20 | |
|---|---|---|---|---|---|---|---|
| Sino-Korean | 일 | 이 | 삼 | 사 | 오 | 십 | 이십 |
| Native Korean | 하나 | 둘 | 셋 | 넷 | 다섯 | 열 | 스물 |
- Native numbers count things, people, age and hours: 사과 세 개, 두 명, 스무 살, 세 시.
- Sino numbers are for money, dates, minutes, floors and phone numbers: 삼천 원, 오 분, 칠 층.
- Native numbers only go to 99. Above that, Sino numbers are used for everything.
Shortened forms before counters
하나, 둘, 셋, 넷, 스물 become 한, 두, 세, 네, 스무 before a counter: 한 개, 두 명, 스무 살.
Big numbers go by 10,000
Korean groups digits by four, not three. 10,000 is 만, so 50,000 is 오만 and 1,000,000 is 백만. 100,000,000 is 억.
FAQ
Why is 10 just 십 and not 일십?
In Sino-Korean, 1 is dropped before 십, 백, 천 and 만: 십, 백, 천, 만. It is kept before 억: 일억.
How do I say phone numbers?
Read each digit with Sino numbers. 0 is 공 in phone numbers: 010-1234 → 공일공 일이삼사.
Why are June and October different?
6월 and 10월 are said 유월 and 시월 (not 육월, 십월) to make them easier to pronounce.