Sino-Korean Numbers 1–100

By the end of this lesson you can:

• Say the 10 root digits of the Sino-Korean number system (일 이 삼 사 오 육 칠 팔 구 십) from memory
• Build and read any number from 1 to 100 using the tens + units pattern (이십 = 20, 이십오 = 25)
• Pick Sino-Korean numbers for their real-world uses: money, dates, phone numbers, minutes, floors, and school grades

TOPIK 1 skills: Sino-Korean numbers

The number system used for dates, money, phone numbers, and addresses. Regular, logical, and fully learnable in one lesson.

RECALL: Two number systems: why two? Korean has two entirely separate number systems: Sino-Korean (this lesson) and Native Korean (Lesson 16). Sino-Korean comes from Chinese and is used for money, dates, phone numbers, addresses, and minutes. Native Korean is used for counting objects, hours, and age. Today is the simpler system, just 10 roots and a pattern.

Part 1 · The 10 Root Digits

일 이 삼 사 오 육 칠 팔 구 십

These 10 words are everything. Every number from 1 to 99 is built from combinations of just these roots. Learn them cold. They are the foundation of the entire system.

Listening drill, 1 to 10 in sequence: audio m1-l14-v44.

TIP: Memory hooks for the trickier ones: 육 (6) sounds a bit like “yuck” (imagine six muddy boots). 칠 (7) is like “chill” (seven ice cubes). 팔 (8) rhymes with “pal” (eight friends). 구 (9) is like “goo” (nine sticky things). Once 1–10 click, the rest of the system builds itself.

Part 2 · The Tens: Pure Logic

십 does all the work.

To make a multiple of ten, you simply put the digit in front of 십 (ten). Twenty is literally “two-ten” (이십), thirty is “three-ten” (삼십), and so on. There are no irregular written forms: the pattern holds perfectly up to 90.

Part 3 · Building 11–99: The Pattern

Tens + units. That’s the whole formula.

To say any number between 11 and 99: say the tens, then say the units. 십일 (11) = ten-one. 이십오 (25) = two-ten-five. 구십구 (99) = nine-ten-nine. The written forms have no exceptions: every number is built exactly by the formula. (One pronunciation shift to know: see the tip below on numbers ending in 육.)

The Construction Formula: [tens digit] × 십 + [units digit]

TIP: One important note about 10 vs 11–19: 십 alone = 10. 십일 = 11. 십이 = 12. Notice: for the teens (11–19) you say 십 + digit, not 일십 (that would mean 1×10, which doesn’t exist). Only 20 and above use a leading digit: 이십, 삼십, etc. Ten itself is just 십.

TIP: Pronunciation shift with 육 (6): when 육 follows 십, ㄴ-insertion plus nasalisation changes the sound. 십육 (16) is pronounced [심뉵] sim-nyuk, and 삼십육 (36) is [삼심뉵] sam-sim-nyuk. The spelling stays perfectly regular. Only the pronunciation shifts.

Part 4 · The Full Grid: 1 to 100

Every number at once. The multiples of 10 are shown in bold. Try reading each row aloud before checking the Korean.

Part 5 · Real-World Uses

When do you use Sino-Korean numbers?

Knowing which number system to use is as important as knowing the numbers. Sino-Korean (this lesson) covers money, dates, phone numbers, minutes, floors, and more.

Part 6 · 숫자 퀴즈 (Number Quiz)

Convert these to Korean. Say the Korean aloud for each number before checking the Answer Key at the end of the lesson.

1. 17
2. 24
3. 36
4. 52
5. 63
6. 78
7. 85
8. 91
9. 100
10. 14
11. 29
12. 44

MILESTONE: 60 items in your active deck. Numbers unlock money, dates, and schedules. Combined with your greetings and polite expressions, you now have real conversational range.

CULTURE: 만: the number that shapes Korean prices. Korea uses 만 (man, 10,000) as its basic large-number unit, not 천 (1,000) like English speakers might expect. This means prices are always expressed in 만 and 천 combinations: 삼만 오천 원 = 35,000 won. When you hear a Korean price, your brain needs to shift to thinking in units of 10,000 rather than 1,000. This trips up English speakers constantly: seeing “35,000” on a menu and mentally reading it as “thirty-five thousand dollars” rather than about $25 USD. The price of a decent restaurant meal in Seoul is around 만 원 to 이만 원 (10,000–20,000 won). A café coffee is about 오천 원 (5,000 won). Once your brain adapts to 만-based thinking, navigating Korean prices becomes second nature. 만 itself is introduced properly in Month 4 when shopping vocabulary arrives.

Homework

Before Lesson 15, the Week 3 Review…

1. Write 일 이 삼 사 오 육 칠 팔 구 십 from memory 5 times each, no looking. Then write 백 (100). These 11 roots are all you need for the entire Sino-Korean system up to 999.
2. Say these numbers aloud as fast as you can, three times through: 11, 15, 23, 37, 42, 56, 68, 74, 89, 93, 100. Time yourself on the third pass. It should take under 20 seconds when fluent.
3. Practice reading prices: 오백 원 (500 won) · 천오백 원 (1,500 won) · 삼천 원 (3,000 won) · 오천 원 (5,000 won) · 만 원 (10,000 won). Note: 천 (1,000) was introduced in the usage table. Use it as a preview for upcoming content.
4. Say today’s date out loud in Korean. Format: [month]월 [day]일. For example, if today is March 15: 삼월 십오일 (sam-wol si-bo-il). Do this every morning as a habit. It locks in both number systems over time.
5. Lesson 15 is the Week 3 Review. It will test all of this week’s vocabulary: greetings (L11), self-introduction (L12), polite expressions (L13), and Sino-Korean numbers (L14). Do a full deck pass tonight. 60 items: you should be clearing most of them quickly by now.

Answer Key

Part 6 · Number Quiz