Japanese numerals


The Japanese numerals are the number names used in Japanese. In writing, they are the same as the Chinese numerals, and the grouping of large numbers follows the Chinese tradition of grouping by 10,000. Two pronunciations are used: the Sino-Japanese readings of the Chinese characters and the Japanese yamato kotoba.

Basic numbering in Japanese

There are two ways of writing the numbers in Japanese: in Arabic numerals or in Chinese numerals. The Arabic numerals are more often used in horizontal writing, and the Chinese numerals are more common in vertical writing.
Most numbers have two readings, one derived from Chinese used for cardinal numbers and a native Japanese reading used somewhat less formally for numbers up to 10. In some cases the Japanese reading is generally preferred for all uses.
NumberCharacterOn readingKun readingPreferred reading
0ichi / いちhito / ひと・つichi
2ni / にfuta / ふた・つni
3san / さんmit / みっ・つsan
4shi / しyon, yot / よん、よっ・つyon
5go / ごitsu / いつ・つgo
6roku / ろくmut / むっ・つroku
7shichi / しちnana / なな・つnana
8hachi / はちyat / やっ・つhachi
9ku, kyū / く, きゅうkokono / ここの・つkyū
10jū / じゅうtō / とおjū
13十三jū-san / じゅうさんjū-san
20二十ni-jū / にじゅうni-jū
30三十san-jū / さんじゅうsan-jū
40四十shi-jū / しじゅうyon-jū
50五十go-jū / ごじゅうgo-jū
60六十roku-jū / ろくじゅうroku-jū
70七十shichi-jū / しちじゅうnana-jū
80八十hachi-jū / はちじゅうhachi-jū
90九十ku-jū / くじゅうkyū-jū
100hyaku / ひゃくhyaku
1,000sen / せんsen
10,000man / まんman
100,000,000oku / おく—oku
1,000,000,000,000chō / ちょう—chō
10,000,000,000,000,000kei / けい—kei

* The special reading maru is also found. It may be optionally used when reading individual digits of a number one after another, instead of as a full number. A popular example is the famous 109 store in Shibuya, Tokyo which is read as ichi-maru-kyū. This usage of maru for numerical 0 is similar to reading numeral 0 in English as oh. It literally means a circle. However, as a number, it is only written as 0 or rei. Additionally, two and five are pronounced with a long vowel in phone numbers.
Starting at 万, numbers begin with 一 if no digit would otherwise precede. That is, 100 is just 百 hyaku, and 1000 is just 千 sen, but 10,000 is 一万 ichiman, not just *man. And, if 千 sen directly precedes the name of powers of myriad, 一 ichi is normally attached before 千 sen, which yields 一千 issen. That is, 10,000,000 is normally read as 一千万 issenman. But if 千 sen does not directly precede the name of powers of myriad or if numbers are lower than 2,000, attaching 一 ichi is optional. That is, 15,000,000 is read as 千五百万 sengohyakuman or 一千五百万 issengohyakuman, and 1,500 as 千五百 sengohyaku or 一千五百 issengohyaku.
The numbers 4 and 9 are considered unlucky in Japanese: 4, pronounced shi, is a homophone for death; 9, when pronounced ku, is a homophone for suffering. See tetraphobia. The number 13 is sometimes considered unlucky, though this is a carryover from Western tradition. In contrast, numbers 7 and sometimes 8 are considered lucky in Japanese.
In modern Japanese, cardinal numbers are given the on readings except 4 and 7, which are called yon and nana respectively. Alternate readings are used in month names, day-of-month names, and fixed phrases. For instance, the decimal fraction 4.79 is always read yon-ten nana kyū, though April, July, and September are called shi-gatsu, shichi-gatsu, and ku-gatsu respectively. The on readings are also used when shouting out headcounts. Intermediate numbers are made by combining these elements:
There are some phonetic modifications to larger numbers involving voicing or gemination of certain consonants, as typically occurs in Japanese : e.g. roku "six" and hyaku "hundred" yield roppyaku "six hundred".
×123456789101001000
100hyaku, ippyakunihyakusanbyakuyonhyakugohyakuroppyakunanahyakuhappyakukyūhyaku———
1,000sen, issennisensanzenyonsengosenrokusennanasenhassenkyūsen———
10itchōnichōsanchōyonchōgochōrokuchōnanachōhatchōkyūchōjutchō*hyakuchōissenchō
10ikkeinikeisankeiyonkeigokeirokkeinanakeihakkeikyūkeijukkei*hyakkei**issenkei

* This also applies to multiples of 10. Change ending -jū to -jutchō or -jukkei.
** This also applies to multiples of 100. Change ending -ku to -kkei.
In large numbers, elements are combined from largest to smallest, and zeros are implied.
NumberCharacterReading
11十一jū ichi
17十七jū nana, jū shichi
151百五十一hyaku go-jū ichi
302三百二san-byaku ni
469四百六十九yon-hyaku roku-jū kyū
2025二千二十五ni-sen ni-jū go

Other types of numerals

Beyond the basic cardinals and ordinals, Japanese has other types of numerals.
Distributive numbers are formed regularly from a cardinal number, a counter word, and the suffix, as in.

Powers of 10

Large numbers

Following Chinese tradition, large numbers are created by grouping digits in myriads rather than the Western thousands :
Rank10101010101010101010101010 or 1010 or 1010 or 1010 or 1010 or 10
Character万億兆京垓?, 秭穣溝澗正載極恒河沙阿僧祇那由他, 那由多不可思議無量大数
Readingmanokuchōkeigaijo, shijōkōkanseisaigokugōgashaasōginayutafukashigimuryōtaisū

Variation is due to Jinkōki, Japan's oldest mathematics text. The initial edition was published in 1627. It had many errors. Most of these were fixed in the 1631 edition. In 1634 there was yet another edition which again changed a few values. The above variation is due to inconsistencies in the latter two editions.
Examples: '
  • 1 0000 : 一万
  • 983 6703 : 九百八十三万 六千七百三
  • 20 3652 1801 : 二十億 三千六百五十二万 千八百一
However, numbers written in Arabic numerals are separated by commas every three digits following English-speaking convention. If Arabic numbers and kanji are used in combination, Western orders of magnitude may be used for numbers smaller than 10,000.
In Japanese, when long numbers are written out in kanji, zeros are omitted for all powers of ten. Hence 4002 is 四千二. However, when reading out a statement of accounts, for example, the skipped digit or digits are sometimes indicated by tobi or tonde : e.g. yon-sen tobi ni or yon-sen tonde' ni instead of the normal yon-sen ni''.

Decimal fractions

Japanese has two systems of numerals for decimal fractions. They are no longer in general use, but are still used in some instances such as batting and fielding averages of baseball players, winning percentages for sports teams, and in some idiomatic phrases, and when representing a rate or discount. The bu fractions are also used when talking about fevers—for example 九度二分 for 9 and two parts—the temperature 9.2°C.
One system is as follows:
Rank10101010101010101010
Character分厘毛糸忽微繊沙塵埃
Readingburinmōshikotsubisenshajinai

This is the system used with the traditional Japanese units of measurement. Several of the names are used "as is" to represent a fraction of a sun.
The other system of representing these decimal fractions of rate or discount uses a system "shifted down" with a bu becoming a "one hundredth" and so on, and the unit for "tenth" becoming wari:
Rank1010101010
Character割分厘毛糸
Readingwariburinmōshi

This is often used with prices. For example:
With the exception of wari, these are rarely seen in modern usage. Decimal fractions are typically written with either kanji numerals or Arabic numerals, preceded by a decimal point, and are read as successive digits, as in Western convention. Note that, in written form, they can be combined with either the traditional system of expressing numerals, in which powers of ten are written, or with the place value system, which uses zero In both cases, however, the reading follows the traditional system

Formal numbers

As with Chinese numerals, there exists in Japanese a separate set of kanji for numerals called daiji used in legal and financial documents to prevent unscrupulous individuals from adding a stroke or two, turning a one into a two or a three. The formal numbers are identical to the Chinese formal numbers except for minor stroke variations. Today, the numbers for one, two, three, and ten are written only in their formal form in legal documents. These numbers' common forms can be changed to a higher value by adding strokes. In some cases, the digit 1 is explicitly written like 壱百壱拾 for 110, as opposed to 百十 in common writing.
Formal numbers:
The four current banknotes of the Japanese yen, 1000-yen, 2000-yen, 5000-yen, and 10000-yen, have formal numbers 千, 弐千, 五千, and 壱万, respectively.

Old Japanese

shares some vocabulary with later periods, but there are also some unique numbers which are not used any more, aside from being parts of specific lexemes.
Notes:
NumberReadingExamplesNotes
1一日 pi1to2pi1, 一年 pi1to2to2se
2二夜 putayo2
3三十 mi1so1
4四十 yo2so1, 四人 yo2tari
5五年 ituto2se
6六爪 mutuma
7七瀬 nanase Often used to mean many.
8八雲 yakumo1 Often used to mean many.
9九柱 ko2ko2no2pasira
10 / 十日 to2woka
10三十 mi1so1, 四十 yo2so1, 六十 muso1, 八十 yaso1 Found only in compound words; not used alone.
20二十 patati, 二十人 patatari, 二十年 patato2se
50五十日 ika
100五百 ipo, 五百年 ipoto2se, 五百夜 ipoyo2, 八百 yapo, 三百 mi1po, 六百 mupo, 九百 ko2ko2no2po Used for multiple hundreds in compound numerals. Often used to mean many.
100百日 mo1mo1ka Used for non-multiple hundred and for the number "100" by itself. Often used to mean many.
1000千年 tito2se Often used to mean many.
10000八百万 yapoyo2ro2du Often used to mean many.

Hand counting

Japanese uses separate systems for counting for oneself and for displaying numbers to others, which both proceed up to ten. For counting, one begins with the palm open, then counts up to five by curling up the fingers, starting from the thumb – thus one has just the thumb down, while four has only the pinkie extended, and five has a fist. One then counts up to ten by proceeding in the reverse order, extending the fingers, starting at the pinkie – thus six is the same as four, seven the same as three, and so forth, with ten ending with the palm open. While this introduces ambiguity, it is not used to present to others, so this is generally not a problem. When displaying for others, one starts with the hand closed, and extends fingers, starting with the index, going to the pinkie, then ending with the thumb, as in the United States. For numbers above five, one uses an open hand and places the appropriate number of fingers from the other hand against the palm – so six has the index finger against the palm, and so forth. To display ten, one presents both hands open and palm outwards.

Numbers in Japanese words

Since the adoption of Arabic numerals, numbers have become written in Arabic numerals more and more often. Counters and ordinal numbers are typically written in Arabic numbers, such as 3人, 7月, 20歳, etc., although 三人、七月、and 二十歳 are also acceptable to write. However, numbers that are part of lexemes are typically written in kanji. For example, the term yaoya 八百屋 translates into "800 store", uses the Old Japanese pronunciation for 800, yao. The notorious Japanese organized crime syndicate, the yakuza, can be written 八九三, a hand in oicho-kabu that is worth 0 points, indicating that yakuza are "worthless persons" or "gambling persons".