Japanese has two ways to count: a native Japanese system and a Sino-Japanese system borrowed from Chinese. Both are used in everyday life, and knowing which one to use in a given situation is just as important as memorizing the words themselves. This guide explains both systems, shows where each one appears in real contexts, and points out the mistakes that trip up most learners.
Two Number Systems: Why Japanese Has Both
Most languages have one counting system. Japanese has two, and both remain in active use. The Sino-Japanese system (also called the on-yomi or Chinese-reading system) is used for dates, money, phone numbers, floors of a building, and most formal counting. The native Japanese system (kun-yomi) is used for counting small quantities of generic objects and appears in certain fixed expressions.
Learners often start with only one system and then feel confused when they hear the other in a shop, on a train platform, or in conversation. Understanding that both exist — and that context determines which to use — removes much of that confusion early on.
Sino-Japanese Numbers: 1 to 10
These are the numbers you will encounter most frequently in written Japanese and in formal speech. They are also the foundation for counting into the hundreds, thousands, and beyond.
| Number | Kanji | Romaji | Pronunciation note |
|---|---|---|---|
| 1 | 一 | ichi | ee-chee |
| 2 | 二 | ni | nee |
| 3 | 三 | san | sahn |
| 4 | 四 | shi / yon | shee / yohn |
| 5 | 五 | go | goh |
| 6 | 六 | roku | roh-koo |
| 7 | 七 | shichi / nana | shee-chee / nah-nah |
| 8 | 八 | hachi | hah-chee |
| 9 | 九 | ku / kyuu | koo / kyoo |
| 10 | 十 | juu | joo |
Notice that 4, 7, and 9 each have two readings. This is not random. The readings shi (4), shichi (7), and ku (9) are considered unlucky in certain contexts because shi sounds like 死 (death), shichi can be confused with ichi in fast speech, and ku sounds like 苦 (suffering). As a result, the alternative readings yon, nana, and kyuu are preferred in phone numbers, hospital room assignments, and other settings where the unlucky association matters. Both readings are correct; the choice depends on context and individual preference.
Native Japanese Numbers: 1 to 10
The native Japanese counting system is older and is used for counting objects in general when no specific counter word is attached. It only runs cleanly from 1 to 10; beyond that, the Sino-Japanese system takes over entirely.
| Number | Kanji | Romaji | Hiragana |
|---|---|---|---|
| 1 | 一つ | hitotsu | ひとつ |
| 2 | 二つ | futatsu | ふたつ |
| 3 | 三つ | mittsu | みっつ |
| 4 | 四つ | yottsu | よっつ |
| 5 | 五つ | itsutsu | いつつ |
| 6 | 六つ | muttsu | むっつ |
| 7 | 七つ | nanatsu | ななつ |
| 8 | 八つ | yattsu | やっつ |
| 9 | 九つ | kokonotsu | ここのつ |
| 10 | 十 | too | とお |
A practical example: if a shop assistant asks how many bags you want and you say futatsu (二つ), that is perfectly natural. You could also say ni-mai using the Sino-Japanese number with the counter for flat objects, but futatsu works for a quick, casual answer when no specific counter is needed.
Numbers 11 to 99: Building on the Base
Once you know 1 to 10 in the Sino-Japanese system, larger numbers follow a straightforward pattern. Japanese combines the tens digit with 十 (juu) and adds the units digit after it. There are no irregular forms like eleven or twelve to memorize.
- 11 = 十一 (juu-ichi)
- 15 = 十五 (juu-go)
- 20 = 二十 (ni-juu)
- 23 = 二十三 (ni-juu-san)
- 47 = 四十七 (yon-juu-nana)
- 99 = 九十九 (kyuu-juu-kyuu)
The pattern is: [tens digit] + 十 + [units digit]. For multiples of ten, you simply drop the units digit. This regularity makes Japanese numbers easier to learn than many European systems once you get past the initial two-system hurdle.
Hundreds, Thousands, and Ten-Thousands
Japanese uses 百 (hyaku) for hundred, 千 (sen) for thousand, and 万 (man) for ten thousand. The ten-thousand unit is important because large numbers in Japanese are grouped in units of ten thousand, not one thousand as in English. This causes real confusion for learners reading price tags or bank figures.
- 100 = 百 (hyaku)
- 200 = 二百 (ni-hyaku)
- 1,000 = 千 (sen)
- 3,000 = 三千 (san-zen) — note the sound change from sen to zen
- 10,000 = 一万 (ichi-man)
- 100,000 = 十万 (juu-man)
- 1,000,000 = 百万 (hyaku-man)
When reading a price of ¥12,500 in Japanese, a native speaker says ichi-man ni-sen go-hyaku (一万二千五百), not twelve thousand five hundred. Grouping mentally in units of 10,000 rather than 1,000 takes practice but becomes natural with exposure.
Some sound changes occur when combining numbers: 300 is san-byaku (not san-hyaku), 600 is roppyaku, and 800 is happyaku. Similarly, 3,000 is san-zen and 8,000 is hassen. These changes follow phonetic rules rather than arbitrary exceptions, and most learners pick them up through repeated listening.
Counter Words: The Part Most Textbooks Skip
In Japanese, you do not simply say a number and a noun. You attach a counter word (助数詞, josuushi) between the number and the noun. The counter changes depending on what you are counting. This is one of the more unfamiliar aspects of the language for English speakers.
Here are some of the most commonly needed counters:
| What you are counting | Counter | Example | Meaning |
|---|---|---|---|
| People | 人 (nin / hitori / futari) | 三人 (san-nin) | three people |
| Flat objects (paper, shirts, tickets) | 枚 (mai) | 二枚 (ni-mai) | two sheets / tickets |
| Long thin objects (pens, bottles, rivers) | 本 (hon) | 一本 (ippon) | one bottle / pen |
| Small animals | 匹 (hiki) | 三匹 (san-biki) | three small animals |
| Large animals, cars | 頭 (tou) | 二頭 (ni-tou) | two large animals |
| Books, bound items | 冊 (satsu) | 五冊 (go-satsu) | five books |
| Floors of a building | 階 (kai) | 三階 (san-kai) | third floor |
| Times / occurrences | 回 (kai) | 二回 (ni-kai) | twice |
Note that 人 (person counter) is irregular for 1 and 2: one person is hitori (一人) and two people is futari (二人), while three or more use the regular Sino-Japanese base plus nin (三人, 四人, etc.).
When you are unsure which counter to use, the native Japanese system (hitotsu, futatsu, etc.) often works as a neutral fallback for generic objects up to ten. Native speakers use this strategy too in casual speech.
Numbers in Everyday Situations
Knowing the numbers in isolation is only part of the picture. Here are the contexts where you will actually need them.
Shopping and prices
Price tags in Japan use Arabic numerals (¥500, ¥1,280), so reading them is straightforward. The challenge comes when a cashier announces a total aloud. Listen for en (円, yen) at the end: sen ni-hyaku hachi-juu en means ¥1,280. If the amount includes tax, the cashier may say zei-komi de (税込みで), meaning the tax is included.
Telling the time
Hours use the Sino-Japanese numbers plus ji (時): ichi-ji (1 o’clock), ni-ji (2 o’clock), and so on. Minutes use fun or pun (分), with some sound changes: 1 minute is ip-pun, 3 minutes is san-pun, 6 minutes is rop-pun. Half past is han (半): ni-ji han means 2:30.
Dates
Months use the Sino-Japanese number plus gatsu (月): ichi-gatsu (January), ni-gatsu (February), and so on. Days of the month use nichi (日) for most days, but the first through tenth — and the fourteenth, twentieth, and twenty-fourth — use irregular forms that partially draw from the native Japanese system. The first is tsuitachi, the second is futsuka, the third is mikka, and the pattern continues with similar irregularities through the tenth.
Phone numbers and addresses
Phone numbers in Japan are read digit by digit using Sino-Japanese numbers. The digit 0 is zero (ゼロ) or rei (零), with zero being more common in everyday speech. Building and room numbers follow the same digit-by-digit pattern.
Common Mistakes and How to Avoid Them
Several patterns catch learners off guard:
- Using shi and ku in phone numbers or hospital settings. Stick to yon and kyuu in these contexts to match the preference of most native speakers and avoid any unintended association with death or suffering.
- Forgetting sound changes. Combinations like san + hyaku → san-byaku and ichi + hon → ippon follow consistent phonetic rules. Listening to native audio repeatedly is more effective than memorizing the changes as exceptions.
- Mixing up the ten-thousand grouping. When reading large numbers aloud, convert mentally to Japanese grouping first. ¥50,000 is go-man en, not fifty thousand yen rendered digit by digit.
- Using the native Japanese system beyond 10. There is no juuichi equivalent in the native system. Beyond ten, use the Sino-Japanese system exclusively.
- Attaching the wrong counter. This takes time. Focus first on the most common counters — mai, hon, nin, kai — and expand gradually. Using hitotsu / futatsu as a fallback is acceptable in casual speech.
If you are building on your Japanese greetings and polite expressions, understanding numbers is one of the next practical steps. You may also find it helpful to review how to introduce yourself in Japanese — numbers come up naturally when giving your age or saying how long you have been in Japan. See the guide How to Introduce Yourself in Japanese: Key Phrases for phrases that pair naturally with number knowledge.
Numbers also appear in polite requests and apologies. When asking for a specific quantity in a shop, it helps to know the right level of formality. The article How to Say Excuse Me in Japanese: Sumimasen and More covers the polite phrases that typically accompany number-based requests in stores and restaurants.
Frequently Asked Questions
Do I need to learn both number systems, or can I use just one?
For practical use, the Sino-Japanese system covers most situations: prices, dates, time, floors, phone numbers, and counting with specific counter words. The native Japanese system (hitotsu, futatsu, etc.) is useful as a fallback when counting objects without a specific counter, and you will hear it in conversation. Learning both is worthwhile, but prioritize the Sino-Japanese system first.
Why does the pronunciation of some numbers change depending on what follows?
Japanese phonology tends to favor smoother sound transitions. When a number ending in a vowel or a specific consonant precedes a counter that starts with certain sounds, the combined pronunciation shifts to reduce awkwardness. For example, ichi + hon becomes ippon because the h sound in hon voices differently after a short consonant. These changes follow consistent patterns and become automatic with enough listening practice.
Is it rude to use the number 4 in Japan?
The number 4 is associated with the word for death (死, shi) when read with the Sino-Japanese reading. This has led to a preference for the alternative reading yon in contexts such as hospital floors, room assignments, and gifts. However, 4 is not avoided in all contexts — it appears freely in addresses, prices, and general speech. Awareness of the preference is useful, but the avoidance is not an absolute rule in modern Japan.
How do I say zero in Japanese?
Zero is most commonly said as zero (ゼロ), using the loanword from English. The native reading rei (零) exists and appears in some formal or technical contexts, such as certain government documents or weather reports. In everyday conversation and when reading out phone numbers or addresses, zero is standard.
At what point do large Japanese numbers stop following a predictable pattern?
The Sino-Japanese number system is highly regular up through the tens of millions and beyond. The key units are 十 (10), 百 (100), 千 (1,000), and 万 (10,000). Above 万, the next major unit is 億 (oku, 100 million), followed by 兆 (chou, 1 trillion). The grouping in units of 10,000 rather than 1,000 is the main structural difference from English and requires a mental adjustment, but the system itself does not become irregular at higher values.
Conclusion
Japanese numbers follow two parallel systems — Sino-Japanese and native Japanese — and the context determines which one to use. The Sino-Japanese system covers most practical situations, from reading prices and telling the time to counting with specific counter words. The native system provides a useful fallback for counting general objects up to ten. Sound changes in combinations like san-byaku or ippon follow consistent phonetic rules rather than arbitrary exceptions. The ten-thousand grouping (万) is the main structural difference from English and is worth getting comfortable with early, since it appears on every price tag and bank statement in Japan. Start with 1 to 10, practice the most common counter words, and build from there.
