Korean Numbers Flashcards: 26 Cards with Audio and Notes

Korean Numbers Flashcards: Study the 26 Cards

Every number card in this deck has a slash. The Sino-Korean form is always on the left of the slash and the native Korean form on the right. Say both aloud before you press Show answer. The lesson behind the deck is Korean numbers, so read it first if a card is new.

How Do I Use These Flashcards?

Use the deck above in four steps. It works with tap, click or keyboard, and nothing plays until you press an audio button.

1. Choose a mode. Start with recognition (Hangul to meaning). Switch to recall (meaning to Hangul) or listening (audio to meaning) once recognition feels easy.
2. Show the answer. Think of the answer first, then press Show answer (or Space). Turn on the romanization toggle only if you need it; the 26-card table below always shows it.
3. Grade yourself. Press Got it if you answered correctly without help, or Not yet if you hesitated or guessed.
4. Finish the session. A session holds up to 20 cards (you can set 10, 20 or 40). With 26 cards, a first-time learner can split the deck over three days, using the default limit of 10 new cards a day.

The Three Study Modes

Recognition shows the Hangul and asks for the meaning, which trains reading. Recall shows the meaning and asks for the Hangul, which trains remembering; you may type the answer with your Hangul keyboard or just recall it in your head. Listening plays a clip and hides the letters, which trains the ear. Listening mode only uses a card once its audio is approved, and cards without approved audio are skipped in that mode with a note.

Got It and Not Yet

Got it moves the card up one Leitner box, so it comes back later. Not yet sends the card back to box 1, so it returns in the same session or within 10 minutes. The grades are your own judgement; the deck does not score you or claim fluency.

Deck Scope: What Is and Is Not Covered

The deck shows the numbers 1 to 20 in both systems, side by side, plus six cue cards that show when each system is used: a clock time, an age, a head count, a price, a date and a phone number. It is the overview deck. The full Sino-Korean set, which goes up to 억 (100 million), is in the Sino Korean numbers flashcards. The full native set, which stops at 99, is in the native Korean numbers flashcards.

What Is Left out of This Deck?

Counter words such as 개, 명, 마리 and 잔 have their own deck, the Korean counters flashcards. Numbers above 20 are not on these cards. For any number, use the Korean number converter, which shows the reading in Hangul.

All 26 Cards in One Table

All 26 cards appear below in deck order. The table is plain HTML, so you can use it as a drill without the deck: cover the Meaning column, read each pair aloud, then uncover the meaning.

Reading the Table

Hangul is the word. Revised Romanization (RR) is a learning aid, so try to read the Hangul before you look at it. RR follows the sound of the word, which is why some spellings change, as in 십육 (simnyuk). The Meaning column gives the English gloss, and the Note column gives a use or sound hint. The last column lists the audio assetId; a second ID marks a slow clip. On cards 1-20 the left side of the slash is Sino-Korean and the right side is native Korean.

Usage Notes for These Cards

Left of the slash or right? Use the left-hand, Sino-Korean form for dates, money, phone numbers, floors and minutes. Use the right-hand, native Korean form for counting objects and people, and for age. A short way to remember it is that Sino numbers label things and native numbers count things.

Both systems in one answer. A clock time needs both. The hour is native and the minute is Sino, so 3:15 is 세 시 십오 분 (se si sibo bun). The first part, 세, is the shortened form of 셋 that native numbers take before a counter. Card 21 drills exactly this.

The teens follow a pattern. Sino 11-19 are 십 plus the unit, as in 십일 and 십이. Native 11-19 are 열 plus the unit, as in 열하나 and 열둘. Once you know 1-10 in both systems, you can build all the teens.

Shops mix the systems. A price takes Sino numbers, but a quantity takes native numbers. 사과 두 개 오천 원 means two apples for 5,000 won: 두 개 counts the apples and 오천 원 states the price.

Which Sounds Do Not Match the Spelling?

십육 is written with ㅂ but said [심뉵]. A ㄴ sound is inserted before 육, and the ㅂ in 십 becomes ㅁ next to it (nasalization). Revised Romanization follows the sound, so the card shows simnyuk.

열일곱 is said [열릴곱]. A ㄴ sound is inserted before 일, and it turns into ㄹ next to the final ㄹ of 열. In the same way 열여덟 is said [열려덜] and 열여섯 is said [열려섣].

열아홉 is said [여라홉]. The final ㄹ of 열 moves onto the empty ㅇ of 아 (liaison). 열하나 is different: its standard pronunciation is [열하나], and the ㅎ only weakens in fast speech, so the card romanizes it yeolhana. Reviewers should confirm these forms against the 국립국어원 standard pronunciation rules.

What Mistakes Do Learners Make with Korean Numbers?

• Using Sino numbers to count objects, such as 이 개 for two items. Say 두 개.
• Using native numbers for dates, such as 오월 다섯 일. The day is 오 일 (the fifth), and the month is 오월.
• Using a Sino number for the hour, such as 삼 시. Hours need the native form, so say 세 시.
• Forgetting that 하나, 둘, 셋 and 넷 shrink before a counter. Say 한 명 and 두 명, not 하나 명 or 둘 명.

Most of these errors come from choosing the wrong system, which is why the cue cards at the end of the deck matter as much as the number pairs.

How Does the Review Schedule Work?

The deck uses a simplified Leitner system with five boxes. A new card starts in box 1. Each Got it moves it up one box, and each Not yet returns it to box 1. The box sets how long the card waits before it is due again.

Each session shows due cards first, oldest due first, and then up to 10 new cards a day by default. A deck of 26 cards is introduced over three days at the default of 10 new cards a day, and the later boxes bring each card back at longer gaps. Progress is saved only in this browser, so clearing site data deletes it. Use the export button to save a small JSON file with card IDs, boxes and due dates, and import it on another device. No account is needed.

Cultural and Practical Context

Korean speakers switch between the two systems without thinking, and the rule of thumb of things you count versus things you label is a common way to teach the split. Learners meet both systems on the first day in Korea: a bus fare is Sino, a request for two coffees is native, and a clock time uses both in the same phrase.

Limits of This Deck

The deck holds 26 cards, so it does not teach numbers above 20, and counters appear only inside the six cue cards (시, 분, 살, 명, 원 and the date units 월 and 일). It does not test whether you can pick the correct system in a new sentence, only whether you recognise and recall the forms. The sound notes for 열넷 and the native teens follow the standard pronunciation rules and were reviewed by Min-ji Park. All Korean text is generated, and Min-ji Park reviewed and signed off the text and audio on 15 October 2026.

Next Steps after This Deck

Continue with the Sino Korean numbers flashcards for the full Sino set, then the native Korean numbers flashcards, and finally the Korean counters flashcards. Write the same words by hand with the Korean numbers worksheet, check yourself with the Korean numbers quiz, or try other numbers in the Korean number converter. The Korean vocabulary flashcards page lists every other deck, and the Korean flashcards hub lists all topics.

Frequently Asked Questions

Which Side of the Slash Is Sino and Which Is Native?

The Sino-Korean number is always on the left of the slash and the native Korean number is on the right. So 일 / 하나 shows Sino 일 first and native 하나 second. Use the left form for dates, money and phone numbers, and the right form for counting objects and people.

Why Does 3:15 Use Both Systems?

Korean clock times use a native number for the hour and a Sino number for the minutes. So 3:15 is 세 시 십오 분: 세 is the native three, 십오 is the Sino fifteen. A handy way to remember it: the hour counts, the minutes label a point on the clock.

How High Can Native Numbers Go?

In modern use native Korean numbers stop at 99, which is 아흔아홉. From 100 onward speakers switch to Sino numbers, so 100 is 백 even when counting objects. This deck only shows native numbers up to 20, and the native numbers deck covers the tens up to 90.

Is There a Quick Rule for Choosing a System?

Yes. Use native numbers for things you count, such as people, objects and age, and Sino numbers for things you label, such as dates, money, phone numbers and floors. The rule has exceptions, such as hours, so check the cue cards at the end of the deck.

Is My Progress Saved If I Close the Page?

Yes, in the same browser on the same device. Card boxes and due dates are stored locally and nothing is sent to a server. Clearing site data, using a private window or switching browsers removes them, so use the export button to keep a backup file. No account is needed.