Korean numbers

Korean has two main number systems: Sino-Korean (based on Chinese) and Native Korean. Sino-Korean numbers (일, 이, 삼, 사, 오, 육, 칠, 팔, 구, 십 (10), 백 (100), 천 (1000), 만 (10000)) are used for dates (years, months, days), phone numbers, prices, measurements, addresses, and counting minutes and seconds. Koreans group numbers into "man" (만 - 10,000) when counting beyond 10,000; for example, 100,000 is "십만" (십 - 10, 만 - 10000).

Native Korean numbers (1, 2, 3, 4, 5, 6, 7, 8, 9, 10: 하나, 둘, 셋, 넷, 다섯, 여섯, 일곱, 여덟, 아홉, 열, followed by 스물 (20), 서른 (30), 마흔 (40), 쉰 (50), 예순 (60), 일흔 (70), 여든 (80), 아흔 (90)) are used for counting objects, people, age (when asking "How old are you?"), and telling time (hours only). For objects, Native Korean numbers are used only up to 99; after that, Sino-Korean numbers are preferred.

A counter word is used after the number: "명" (myeong) for people (e.g., 두 명 - two people), "개" (gae) for general objects (e.g., 세 개 - three things), "마리" (mari) for animals (e.g., 다섯 마리 - five animals), "병" (byeong) for bottles (e.g., 아홉 병 - nine bottles), and "권" (gwon) for books (e.g., 일곱 권 - seven books). When using Native Korean numbers with counters, 하나, 둘, 셋, and 넷 change to 한, 두, 세, and 네 respectively (e.g., 한 명, 두 개, 세 마리, 네 병). For telling time, use Native Korean numbers for hours (e.g., "세 시" - three o'clock) and Sino-Korean for minutes (e.g., "오십 분" - fifty minutes).