Korean numbers: Sino-Korean and native Korean, explained

Korean has two complete sets of numbers, and you need both. One arrived from Chinese centuries ago — these are called Sino-Korean numbers — and the other is native Korean, older than the borrowing. English does something similar when it counts “one, two, three” but switches to Latin for “primary, secondary, tertiary.” The difference is that in Korean, both sets are part of daily life, and the situation decides which one you reach for.

The systems themselves are small: ten words each, plus a few building blocks. The rules for choosing between them are consistent, and they become automatic faster than you'd expect. By the end of this page you can count to 999, give your age, and read a clock — and you can test yourself right here, no account needed.

Sino-Korean numbers run on ten words. Learn these and you can already read most of the numbers you'll meet in Korea — prices, dates, bus routes, phone numbers.

From 11 upward there is nothing new to memorize — you stack what you have. Eleven is 십일 (ten-one). Twenty is 이십 (two-ten). Twenty-five is 이십오 (two-ten-five). The pattern holds as far as you want to go.

Larger numbers add three more words: 백 (100), 천 (1,000), and 만 (10,000). One caution: Korean drops the 일 in front of these. A hundred is just 백 — never 일백.

Step through numbers below and watch how the pieces stack.

The native numbers are the older, homegrown set. Where Sino-Korean handles the paperwork of life — money, dates, measurements — native numbers handle the physical world: things you can point at and count, hours on the clock, how old you are.

The tens have their own names, which is the main memorization work on this side:

Combining works exactly like Sino-Korean: 열하나 is 11, 스물다섯 is 25. Native numbers stop at 99 — past that, Koreans switch to Sino-Korean even when counting objects. Nobody counts a hundred apples the native way.

This is the question every learner asks, and the honest answer is that the situation decides — and the split is consistent enough that it stops feeling arbitrary within a few weeks of practice.

Hear the split in real sentences:

Korean rarely counts a noun bare. Between the number and the thing sits a counter— a word that classifies what's being counted. English does this in places (“two sheets of paper”); Korean does it for almost everything.

Before a counter, four native numbers shorten: 하나 → 한, 둘 → 두, 셋 → 세, 넷 → 네. Twenty changes too — 스물 → 스무 — but only for exactly twenty; 21 is 스물한.

The counters you'll use first:

The clock is where the two systems meet in a single phrase, which makes it the best practice there is. Hours are native; minutes are Sino-Korean.

Reading about numbers and producing them are different skills. Type these from memory — the box composes Hangul as you go, so you don't need a Korean keyboard installed. The context line tells you which system the situation calls for.