πŸ”’
Grammar

Korean Has TWO Number Systems β€” Here's Why

πŸ“… March 2026β€’ ⏱ 5 min readβ€’ By VLLANG

One of the first things that trips up Korean learners: you learn the numbers 일, 이, μ‚Ό (1, 2, 3) β€” and then someone asks your age and suddenly those numbers are completely wrong. That's because Korean has two separate number systems, and knowing which one to use is essential for sounding natural.

The Two Systems at a Glance

Sino-Korean πŸ‡¨πŸ‡³

일1
il
이2
i
μ‚Ό3
sam
사4
sa
였5
o
μ‹­10
sip
λ°±100
baek
천1,000
cheon

Native Korean πŸ‡°πŸ‡·

ν•˜λ‚˜1
hana
λ‘˜2
dul
μ…‹3
set
λ„·4
net
λ‹€μ„―5
daseot
μ—΄10
yeol
슀물20
seumul
μ„œλ₯Έ30
seoreun

When to Use Each System

SituationSystemExample
Dates & monthsSino-Koreanμ‚Όμ›” (March = 3rd month)
Money & pricesSino-Korean였천 원 (5,000 won)
Phone numbersSino-Korean곡-일-곡...
Floor numbersSino-Koreanμ‚Ό μΈ΅ (3rd floor)
Age (formal)Sino-Koreanμ΄μ‹­μ˜€ μ„Έ (25 years old)
Age (casual)Native KoreanμŠ€λ¬Όλ‹€μ„― μ‚΄ (25 years old)
Counting objectsNative Korean사과 두 개 (2 apples)
Hours of timeNative Korean두 μ‹œ (2 o'clock)
Minutes of timeSino-Koreanμ‚Όμ‹­ λΆ„ (30 minutes)
People in a groupNative Koreanμ„Έ λͺ… (3 people)

⏰ Classic example: "It's 2:30" in Korean = 두 μ‹œ (native: 2 o'clock) μ‚Όμ‹­ λΆ„ (Sino: 30 minutes). Two systems in one sentence!

Why Does Korean Have Two Systems?

Sino-Korean numbers came from Chinese (via Classical Chinese influence) over a thousand years ago, similar to how English borrowed Latin and French words. Native Korean numbers are the original Korean counting system.

Over time, both systems stuck β€” but they naturally divided into different roles. Sino-Korean became dominant for larger numbers and formal contexts, while native Korean stayed for everyday counting of things and people.

The One Rule That Trips Everyone Up

Native Korean numbers 1–4 change form when followed by a counter word:

This is one of the trickiest parts of Korean numbers β€” but once you see the pattern, it clicks fast.

The Easy Shortcut for Beginners

If you're just starting out, learn Sino-Korean first (일, 이, μ‚Ό...) β€” it covers money, dates, and phone numbers, which you'll use constantly as a traveler or beginner. Then gradually add native Korean numbers as you get comfortable.

Practice Korean Numbers + 90 More Words πŸ”’

Our 100 Korean Words guide covers numbers, greetings, food, travel and more β€” with example sentences and practice questions.

Get the Guide on Gumroad β†’