Japanese numerals


The Japanese numerals are numerals that are used in Japanese. In writing, they are the same as the Chinese numerals, and large numbers follow the Chinese style of grouping by 10,000. Two pronunciations are used: the Sino-Japanese readings of the Chinese characters and the Japanese .

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. Archaic readings are marked with †.
NumberCharacter reading readingPreferred reading
0 /
1
2
3
4,
5
6
7
8
9,
10
20†
30†
40†
50†
60†
70†
80†
90†
100†
500†
800†
1,000†
10,000†
100,000,000—
1,000,000,000,000—
10,000,000,000,000,000—

* The special reading 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 . This usage of for numerical 0 is similar to reading numeral 0 in English as oh. However, as a number, it is only written as 0 or. Additionally, two and five are pronounced with a long vowel in phone numbers.
As noted above, and are preferred to and. It is purported that this is because is also the reading of the word, which makes it an unlucky reading ; while may sound too similar to , or . However, in quite a number of established words and phrases, and are preferred; additionally, when counting, and may be preferred.
The number 9 is also considered unlucky; when pronounced, it is a homophone for. The number 13 is sometimes considered unlucky, though this is a carryover from Western tradition. In contrast, 7 and sometimes 8 are considered lucky in Japanese.
In modern Japanese, cardinal numbers except 4 and 7 are generally given the readings. Alternate readings are used in month names, day-of-month names, and fixed phrases; for instance, April, July, and September are called , , and respectively. The readings are also used when shouting out headcounts.
Larger numbers are made by combining these elements:
  • Tens from 20 to 90 are "" as in to.
  • Hundreds from 200 to 900 are "".
  • Thousands from 2000 to 9000 are "".
Starting at a myriad, numbers begin with if no digit would otherwise precede. That is, 100 is just, and 1000 is just, but 10000 is, not just *. And, if directly precedes the name of powers of myriad, is normally attached before, which yields. That is, 10,000,000 is normally read as. But if does not directly precede the name of powers of myriad, attaching is optional. That is, 15,000,000 is read as or, just as 1500 is read as or.
There are some phonetic modifications to larger numbers involving voicing or gemination of certain consonants, as typically occurs in Japanese : e.g. "six" and "hundred" yield "six hundred".
×123456789101001000
100———
1,000———
10*
10***

* This also applies to multiples of 10. Change ending to or.

** This also applies to multiples of 100. Change ending to.
In numbers above 10, elements are combined from largest to smallest, and zeros are implied. Japanese numerals are multiplicative additive rather than positional; to write the number 20 you get the character for two and then the character for ten to get two tens or twenty.
NumberCharacterReadingBasic Meaning
11十一Ten and One
17十七Ten and Seven
151百五十一Hundred, Five Tens and One
302三百二Three Hundreds and Two
469四百六十九Four Hundreds, Six Tens and Nine
2025二千二十五Two Thousands, Two Tens and Five

Strings of digits and decimal numbers

The above digits from 1 to 9 are used primarily in isolation. Strings of digits make use of slightly different readings, with lengthened vowels, for 2 and 5, and less frequently, 4 and 9. This is because when digits are enumerated, if possible, they must be so in groups of two, each of which must consist of exactly four morae, which necessitates the lengthening of normally unimoraic digits such as ni, go, shi and ku. For example, such string as 54'262 is pronounced gō-yon nī-roku ni, with the first two groups being quadrimoraic. The accent is placed on the penultimate mora of each group if possible, hence.
This rule also applies to the last digit of the integer part and all the digits of the decimal part of a decimal number. For example, such decimal number as 252'.255 is pronounced nihyaku gojū nī-ten nī-gō go, with ten meaning "point".

Other types of numerals

For ordinal numbers, see Japanese counter word#Ordinal numbers.
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 into myriads rather than the Western thousands :
Rank10101010101010101010101010
10
10
10
10
Character, ,
Reading,

Variation is due to the, Japan's oldest mathematics text. The initial edition was published in 1627 and had many errors, most of which 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. There are different characters for 10, and after 10 they differ in whether they continue increasing by a factor of 10 or switch to 10.
The first three numbers with multisyllabic names and variation in assigned values ultimately derive from India, though they did not have defined values there. was originally used in Buddhist scripture for an indefinitely large quantity; it derives from the Sanskrit गङ्गा 'Ganges' and, referring to the innumerable sands of the Ganges River., from Sanskrit असंख्येय 'uncountable/innumerable', with the negative prefix, and is from Sanskrit नयुत/नयुतः. After that, the numbers are Buddhist terms translated into or coined in Chinese and later assigned numerical values: and.
Examples:
  • 1 0000 :
  • 983 6703 :
  • 20 3652 1801 :
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 : e.g. or instead of the normal.

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 such as, and when representing a rate or discount. The fractions are also used when talking about fevers—for example for 9 and two parts—referring to the temperature 39.2°C.
One system is as follows:
Rank10101010101010101010
Character
Reading

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 cun |.
The other system of representing these decimal fractions of rate or discount uses a system "shifted down" with a becoming a "one hundredth" and so on, and the unit for "tenth" becoming :
Rank1010101010
Character
Reading

This is often used with prices. For example:
With the exception of, 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