Korean Language Overview

Korean Numbers Made Simple

Korean looks “hard” because there are multiple number systems and special forms: Sino-Korean (일, 이, 삼…), Native Korean (하나, 둘, 셋…), ordinals (첫째/둘째…), and formal labels (제1/제2…). The good news: each form has a predictable “home.” This page maps them at a glance.

1) Two Number Systems: When to Use Which

Use case	Preferred system	Examples
Dates / years, months, days	Sino-Korean	2025년 12월 17일, 3월, 10일
Money, prices, phone digits, IDs	Sino-Korean	5천 원, 3만 원, 010-1234-5678
Minutes/seconds, floor numbers, math	Sino-Korean	15분, 30초, 2층, 3+4=7
Counting things with counters (1–99)	Native Korean (common)	사과 세 개, 사람 두 명, 책 한 권
Hours (telling time)	Native Korean	두 시, 다섯 시 (but minutes use Sino)

Core rule for time: hours = Native
minutes/seconds = Sino

Example: 3:20 → 세 시 이십 분.

2) Quick Reference: 1–10 (Most Used Forms)

Number	Sino-Korean	Native Korean	Common “counter” form
1	일	하나	한 (한 개/한 명/한 권)
2	이	둘	두
3	삼	셋	세
4	사	넷	네
5	오	다섯	다섯
6	육	여섯	여섯
7	칠	일곱	일곱
8	팔	여덟	여덟
9	구	아홉	아홉
10	십	열	열

Native Korean often changes shape before counters: 하나→한, 둘→두, 셋→세, 넷→네, 스물→스무(rarely needed at first).

3) Ordinals: “First / Second / 3rd…”

A. Daily speech (counting order)

첫째 / 첫 번째 = first

둘째 / 두 번째 = second

셋째 / 세 번째 = third

넷째 / 네 번째 = fourth

B. Formal labels (documents, rules, items)

Use 제 + Sino-Korean: 제1조(Article 1), 제2장(Chapter 2), 제3회(3rd event).

This is the “official” style you see in writing.

4) Time, Dates, and Common Gotchas

A. Telling time

1:00 한 시 / 2:10 두 시 십 분 / 6:30 여섯 시 삼십 분 / 12:05 열두 시 오 분.

(Hours are usually Native; 11 and 12 often appear as 열한/열두 in daily usage.)

B. Counting with counters

Counters are “unit words” like 개(things), 명(people), 잔(cups), 권(books), 마리(animals).

Native Korean is most common for 1–99: 사과 한 개, 학생 두 명, 물 세 잔.

In formal contexts, Sino can appear too, but beginners can start with Native safely.

C. Digit-by-digit reading

Phone numbers, account numbers, and many codes are read digit by digit with Sino: 3-1-0-4 → 삼-일-영-사.

(영/공 both mean “0”; 영 is common in reading numbers aloud.)