Korean uses two number systems: native Korean numbers (하나, 둘, 셋, 넷, 다섯...) and Sino-Korean numbers (일, 이, 삼, 사, 오...). Each system is used in specific situations, and mixing them up is one of the most common mistakes Korean learners make.

Telling Time in Korean

Korean time uses both number systems together. Hours use native Korean with the counter 시: 한 시 (1 o'clock), 두 시 (2 o'clock), 세 시 (3 o'clock). Minutes use Sino-Korean with 분: 일 분 (1 minute), 십 분 (10 minutes), 삼십 분 (30 minutes). So 3:25 is 세 시 이십오 분.

Korean Phone Numbers

Phone numbers in Korean are read digit by digit using Sino-Korean numbers. The key difference is that zero is pronounced 공 (gong), not 영. A number like 010-1234-5678 becomes 공일공-일이삼사-오육칠팔.

Money and Prices in Korean

Korean currency (원, won) always uses Sino-Korean numbers. Prices use the standard place value markers: 십 (10), 백 (100), 천 (1,000), 만 (10,000). So 45,000원 is 사만 오천 원.

Dates in Korean

Dates use Sino-Korean numbers throughout. Years use 년 (이천이십사년 = 2024), months use 월 (구월 = September), and days use 일 (십오일 = 15th). September 15, 2024 is 이천이십사년 구월 십오일.

Age in Korean

When talking about age with 살, Korean uses native Korean numbers. Unlike the contracted forms used for counting, age uses full forms: 스물다섯 살 (25 years old), 서른 살 (30 years old), 마흔 살 (40 years old).

Counting Objects and People

Counting uses native Korean numbers with counters. Objects use 개: 한 개, 두 개, 세 개. People use 명: 한 명, 두 명, 세 명. Note that numbers 1-4 contract before counters (하나→한, 둘→두, 셋→세, 넷→네).

Floor Numbers in Korean

Building floors use Sino-Korean numbers with 층: 일 층 (1st floor), 이 층 (2nd floor), 십 층 (10th floor). This is consistent with other formal counting contexts.

Months and Days Duration

Duration of months uses Sino-Korean with 개월: 일 개월 (1 month), 육 개월 (6 months). However, days 1-10 have special native Korean forms: 하루 (1 day), 이틀 (2 days), 사흘 (3 days), 나흘 (4 days), 닷새 (5 days), 엿새 (6 days), 이레 (7 days), 여드레 (8 days), 아흐레 (9 days), 열흘 (10 days).

Practice Makes Perfect

This free Korean numbers practice tool helps you master both number systems through interactive exercises. Listen to Korean numbers and type the digits, or see the digits and build the Korean. With practice across all these real-world scenarios, using the right number system will become automatic.