Numbers and Counting in Japanese

In Brief

Japanese uses いち、に、さん and the rest of the Sino-Japanese number series for ordinary numbers, prices, phone numbers, and numbers above ten. For a general number of objects from one to ten, you can often use the native forms ひとつ、ふたつ、みっつ. In many other situations, a number is followed by a counter—a word that identifies what kind of thing is being counted.

Overview

Numbers are an A1 foundation in Japanese. You need them to understand prices, give a phone number, state a date, order several items, and say how many things there are. The basic pattern is regular enough to build large numbers from a small set of parts, but several common numbers have more than one reading.

Japanese has two number traditions that meet in everyday speech. The Sino-Japanese series—いち、に、さん、し／よん、ご—is the main system for calculation and for building larger numbers. A native Japanese series survives most clearly in the general counting forms ひとつ through とお. These forms count unspecified or ordinary objects without a separate counter.

English can normally place a bare number directly before a plural noun: “three apples.” Japanese nouns do not become plural in the same way. Instead, Japanese commonly combines a number with a counter, as in りんごを三つ (“three apples”) or 学生が三人 (“three students”). This article establishes the number system and the general ～つ forms; specialized counters are the next step.

How It Works

The basic numbers: 0–10

Number	Kanji	Usual reading	Other common reading or use
0	零／〇	ゼロ, れい	ゼロ is common in strings of digits; れい occurs in formal or fixed contexts
1	一	いち	—
2	二	に	—
3	三	さん	—
4	四	よん	し in some fixed combinations
5	五	ご	—
6	六	ろく	—
7	七	なな	しち in some fixed combinations
8	八	はち	—
9	九	きゅう	く in some fixed combinations
10	十	じゅう	—

For isolated numbers and digit strings, よん、なな、きゅう are often the clearest choices for 4, 7, and 9. However, readings cannot always be selected freely. Established expressions include 四月（しがつ） “April,” 七月（しちがつ） “July,” and 九月（くがつ） “September.” Learn the reading together with each counter or time expression.

Building 11–99

Numbers from 11 to 19 are “ten + unit”:

• 11: 十一（じゅういち）
• 14: 十四（じゅうよん）
• 19: 十九（じゅうきゅう）

Multiples of ten are “unit + ten.” Do not add 一 before ten:

Number	Japanese	Reading
10	十	じゅう
20	二十	にじゅう
35	三十五	さんじゅうご
47	四十七	よんじゅうなな
99	九十九	きゅうじゅうきゅう

The same logic continues through larger units: say each non-zero digit before its place value, except that 一 is normally omitted before 十、百、千 when they mean 10, 100, and 1,000.

Hundreds, thousands, and ten-thousands

Value	Kanji	Reading
100	百	ひゃく
200	二百	にひゃく
300	三百	さんびゃく
400	四百	よんひゃく
600	六百	ろっぴゃく
800	八百	はっぴゃく
1,000	千	せん
3,000	三千	さんぜん
8,000	八千	はっせん
10,000	一万	いちまん

The sound changes in 三百、六百、八百、三千、八千 make pronunciation smoother. They are standard forms, not optional accents.

A key difference from English appears at 10,000. English groups large numbers around “thousand” and “million,” while Japanese uses 万（まん）, a unit of ten thousand. Thus 二万 is 20,000, and 十万 is 100,000. For example:

• 1,234: 千二百三十四（せんにひゃくさんじゅうよん）
• 12,345: 一万二千三百四十五（いちまんにせんさんびゃくよんじゅうご）
• 100,000: 十万（じゅうまん）

Counting ordinary objects with ～つ

The native Japanese forms below work as a general-purpose way to count many objects from one to ten. They are complete counting words: do not attach another つ to them.

Quantity	Form	Reading
1	一つ	ひとつ
2	二つ	ふたつ
3	三つ	みっつ
4	四つ	よっつ
5	五つ	いつつ
6	六つ	むっつ
7	七つ	ななつ
8	八つ	やっつ
9	九つ	ここのつ
10	十	とお
how many?	幾つ	いくつ

These readings must be learned as a set; forms such as ひとつ cannot be predicted simply by reading 一 as いち. ～つ is useful when the category is obvious or when no more specific counter is needed. It is not the normal choice for people, clock time, flat sheets, long objects, or many other categories that have established counters.

The quantity often appears after the noun and its particle (a short marker showing the noun’s role):

りんごを三つください。
りんご + を + 三つ + ください
“Please give me three apples.”

A quantity can also modify a noun with の: 三つの質問 means “three questions.” In everyday sentences, 質問が三つあります (“There are three questions”) is also natural.

Prices and yen

Attach 円（えん） directly to the Sino-Japanese number:

• 百円（ひゃくえん） — 100 yen
• 五百円（ごひゃくえん） — 500 yen
• 千二百円（せんにひゃくえん） — 1,200 yen
• 一万円（いちまんえん） — 10,000 yen

Ask いくらですか for a price: これはいくらですか。 (“How much is this?”). In fast speech, sound boundaries may blur, but the written number structure stays the same.

Phone numbers and other digit strings

Phone numbers, room numbers, codes, and similar identifiers are normally read one digit at a time rather than as a single large number. A hyphen may be read の:

090-1234-5678
ゼロきゅうゼロのいちにさんよんのごろくななはち

For clarity, speakers often prefer よん over し and なな over しち in digit strings. The question 電話番号は何番ですか asks “What is your phone number?” Here 何番（なんばん） means “what number.”

Dates: the basic connection

Numbers also form months and calendar dates, but dates contain fixed readings. Months are number + 月（がつ）, with 四月（しがつ）, 七月（しちがつ）, and 九月（くがつ） requiring special attention. Days of the month have many native or irregular forms, including 一日（ついたち）, 二日（ふつか）, 三日（みっか）, 四日（よっか）, and 十日（とおか）. Treat these as vocabulary rather than applying the ordinary number reading mechanically.

Examples in Context

Japanese	Romanization	English	Note
一、二、三、四、五	ichi, ni, san, yon, go	1, 2, 3, 4, 5	Basic Sino-Japanese series
りんごを三つください。	Ringo o mittsu kudasai.	Three apples, please.	General ～つ counting form
質問が二つあります。	Shitsumon ga futatsu arimasu.	I have two questions.	Literally, “There are two questions”
これはいくらですか。	Kore wa ikura desu ka.	How much is this?	Standard price question
百円です。	Hyaku-en desu.	It is 100 yen.	Number + 円
コーヒーは四百五十円です。	Kōhī wa yonhyaku gojū-en desu.	The coffee is 450 yen.	400 + 50 + yen
この町の人口は二万人です。	Kono machi no jinkō wa ni-man nin desu.	This town has a population of 20,000.	万 represents 10,000
電話番号は何番ですか。	Denwa bangō wa nanban desu ka.	What is your phone number?	何番 asks which number
部屋は三〇五号室です。	Heya wa san-zero-go gōshitsu desu.	The room is 305.	Room numbers are read digit by digit
ケーキを八つ作りました。	Kēki o yattsu tsukurimashita.	I made eight cakes.	General object count
箱の中に一つだけあります。	Hako no naka ni hitotsu dake arimasu.	There is only one in the box.	だけ means “only”
四月九日に日本へ行きます。	Shigatsu kokonoka ni Nihon e ikimasu.	I am going to Japan on April 9.	Both month and day use fixed readings
全部で九十九ページです。	Zenbu de kyūjūkyū pēji desu.	It is 99 pages in total.	Regular tens-and-units pattern

Common Mistakes

Reading every 4, 7, and 9 the same way

• Wrong: よんがつ for 四月
• Right: しがつ
• Why: 4, 7, and 9 have alternative readings, and fixed combinations choose a particular one. Months use しがつ、しちがつ、くがつ for April, July, and September.

Building tens in English order

• Wrong: じゅうさん for 30
• Right: さんじゅう
• Why: 十三（じゅうさん） is 13: ten + three. 三十（さんじゅう） is 30: three tens.

Using regular sounds for irregular hundreds

• Wrong: さんひゃく, ろくひゃく, はちひゃく
• Right: さんびゃく、ろっぴゃく、はっぴゃく
• Why: These three hundreds undergo standard sound changes. Memorize them aloud, not only by sight.

Adding ～つ to an ordinary number reading

• Wrong: いちつ、につ、さんつ
• Right: ひとつ、ふたつ、みっつ
• Why: The general object forms belong to the native Japanese series and have their own readings.

Using ～つ for every kind of noun

• Wrong: 学生がみっついます。
• Right: 学生が三人います。 (“There are three students.”)
• Why: People take the counter 人. Many categories have dedicated counters; ～つ is only a general object-counting option.

Treating 万 as “one thousand”

• Wrong: interpreting 一万 as 1,000
• Right: 一万 = 10,000
• Why: Japanese large-number grouping centers on units of four digits. When reading prices and statistics, pause and convert 万 carefully.

Usage Notes

Arabic numerals are extremely common in modern Japanese: 3人, 500円, and 4月9日 appear alongside kanji forms such as 三人 and 五百円. The choice of script does not remove reading changes: 300円 is still さんびゃくえん.

In careful speech, especially over the phone, distinct readings help prevent confusion. ゼロ、よん、なな、きゅう are often easy to distinguish, but institutional or fixed language may favor れい、し、しち、く. Listen to the whole expression rather than expecting one universal reading for each digit.

The ～つ series sounds natural for many everyday objects and abstract items, such as tasks, questions, choices, or reasons. A specific counter can be more informative when one exists. Choosing counters is not merely formal grammar; it is part of ordinary vocabulary.

Beyond the Basics / Advanced Use

You do not need to master all of this at A1, but larger numbers reveal the full Japanese grouping system. Above 万 come 億（おく）, 100 million, and 兆（ちょう）, one trillion. Because English changes named units every three digits while Japanese changes major units every four, direct mental translation becomes unreliable. Group the written number from the right in sets of four when reading Japanese figures.

Decimals use 点（てん） for the decimal point, followed by individual digits: 3.14 is 三点一四（さんてんいちよん）. Fractions commonly use the denominator first: 三分の一（さんぶんのいち） is “one third,” literally “one of three parts.” Zero can be ゼロ or 零（れい）, depending on context and register.

Counting also triggers many sound changes beyond the basic number system. For example, “one item” with 個 is 一個（いっこ）, “one long object” with 本 is 一本（いっぽん）, and “one person” is the irregular 一人（ひとり）. These forms belong to the counter system, so learn number and counter together as a spoken unit.

Some native counting vocabulary extends beyond the general ～つ list in set expressions, dates, and age words. Such forms are historical and cannot always be predicted from modern いち、に、さん. Recognition grows naturally as you study dates, age, counters, and idioms.

Practice Tips

1. Build numbers in both directions. Write five random numbers under 10,000, read them aloud in Japanese, then hear or record Japanese numbers and write the digits. Include 300, 600, 800, 3,000, and 8,000 frequently.
2. Count real objects. Put ten small items on a table and count ひとつ through とお. Then ask yourself いくつありますか and answer in a full sentence.
3. Use practical number sets. Practice prices, a fictional phone number, room numbers, and dates. Keep digit-by-digit readings separate from quantity readings so that 305 can become さんゼロご as a room number but さんびゃくご as a quantity.

Related Concepts

• Next step: Basic Counters — learn 人、個、枚、本、匹、冊 and the sound changes they cause.
• Next step: Time Expressions — use numbers with hours, minutes, weekdays, and calendar expressions.