Numbers, time and dates in Japanese

Ten thousand is a unit of its own

English groups digits in threes and names every third step: thousand, million, billion. Japanese groups them in fours, and the step after 千(せん), a thousand, is a word of its own: 万(まん), ten thousand. So 10,000 is 一万(いちまん), one 万(まん), and there is no way to build it from the word for a thousand. It helps to move the comma in your head: written as 1,0000, the number reads itself.

A hundred thousand is ten ten-thousands

Once 万(まん) is the unit, everything up to a hundred million is counted in it. 100,000 is ten of them, 十万(じゅうまん), and 350,000 is thirty-five, 三十五万(さんじゅうごまん). Translated word by word, “a hundred thousand” lands on a number Japanese does not have. To read a long figure, split it into fours from the right, not into threes.

A million is a hundred ten-thousands

A million is a hundred 万(まん): 百万(ひゃくまん). There is no separate word for it, and ten million is a thousand 万(まん), 千万(せんまん). Both come up wherever large sums are talked about — rents, salaries, the price of a car — and in all of them the English million is the wrong yardstick.

A billion is ten hundred-millions

After 万(まん) the next unit is 億(おく), a hundred million: a one with eight noughts. A billion is ten of them, 十億(じゅうおく). After 億(おく) comes 兆(ちょう), a million million, which is an English trillion. A figure given in 億(おく) is easy to misread by a factor of ten, and on a budget or a balance sheet that is not a small mistake.

No one before a hundred

English says “one hundred” and “one thousand”; Japanese says and writes just 百(ひゃく) and 千(せん). Ten is the same: 十(じゅう), never with 一(いち). Before 万(まん), though, the one comes back: ten thousand is always 一万(いちまん), never 万(まん) on its own. With large sums of money you will also hear 一千万(いっせんまん) for ten million, where the one makes the figure unmistakable.

Three hundred changes its sound

The word for a hundred, ひゃく, changes its first sound after three: 三百(さんびゃく). This is not a stray exception but one habit of Japanese — sounds bending into each other at a join — and it comes back with minutes, with the days of the month and with almost every counter. Learn the hundreds as a row of nine words rather than as nine sums: only three, six and eight are irregular, and they are the ones you will need most often in a shop.

Six hundred and eight hundred

Six and eight lose their last syllable before 百(ひゃく); a small っ doubles the consonant that follows, and ひゃく becomes ぴゃく: 六百(ろっぴゃく), 八百(はっぴゃく). Every other hundred is the plain digit plus ひゃく, including four, seven and nine: 四百(よんひゃく), 七百(ななひゃく), 九百(きゅうひゃく).

Three thousand and eight thousand

The thousands have their own pattern, and it is not the same as the hundreds: three gives 三千(さんぜん), eight gives 八千(はっせん), and six stays regular, 六千(ろくせん). Learn the two rows together — three, six and eight before a hundred and before a thousand — because that is where they get mixed up.

Four o’clock has a short four

Four has the readings よん and し, and before a few counters a third, short one: よ. Hours are one of them, 四時(よじ); so are years, 四年(よねん), and yen, 四円(よえん). In plain numbers and with minutes it is よん: 四十(よんじゅう), 四百(よんひゃく), 四分(よんぷん). Among the months, April takes し: 四月(しがつ).

Nine and seven o’clock: the old readings

The hours take the older readings of nine and seven: 九時(くじ) and 七時(しちじ), where plain counting says きゅう and なな. The months do the same — 九月(くがつ), 七月(しちがつ) — so one rule covers both. Minutes do not: nine minutes is 九分(きゅうふん), seven minutes 七分(ななふん).

Morning and afternoon come first

English puts a.m. and p.m. after the time; Japanese puts 午前(ごぜん), before noon, and 午後(ごご), after noon, in front of it — the larger unit first, as in a date. In conversation they are often left out when the context makes them obvious. Midnight is 午前零時(ごぜんれいじ), twelve noon 正午(しょうご), and announcements count the hour after noon as 午後零時(ごごれいじ), where English says twelve.

Minutes change their sound

The counter for minutes, 分(ふん), becomes ぷん after one, three, four, six, eight and ten: 一分(いっぷん), 三分(さんぷん), 四分(よんぷん), 六分(ろっぷん), 八分(はっぷん), 十分(じゅっぷん). After two, five, seven and nine it stays ふん. Ten minutes is also じっぷん, the older form, and eight minutes also はちふん. Mind the spelling: 十分(じゅっぷん), ten minutes, is written exactly like 十分(じゅうぶん), enough.

Minutes to the hour go last

English names the minutes first and the hour last. Japanese always starts with the hour and adds 前(まえ), before, at the very end: 三時(さんじ)十分(じゅっぷん)前(まえ) is ten to three. Nobody has to use it — 二時(にじ)五十分(ごじゅっぷん) is just as correct — but for five, ten and fifteen minutes to the hour it is very common. There is no word for a quarter: a quarter past three is 三時(さんじ)十五分(じゅうごふん).

April, July and September

The months have no names; they are numbered, month one to month twelve, with 月(がつ) after the number. Three of them read their number differently from plain counting: 四月(しがつ) (April), 七月(しちがつ) (July) and 九月(くがつ) (September). The other nine use the reading you count with.

The first of the month has a name

The days from the 1st to the 10th have old native names: 一日(ついたち), 二日(ふつか), 三日(みっか) and so on up to 十日(とおか). 一日(いちにち) exists as well, written the same way, but it means one day, a stretch of time. From the 11th on, the days are counted with 日(にち).

The 4th and the 8th sound alike

Two of the old day names sound alike: 四日(よっか) is the 4th, 八日(ようか) the 8th. The difference is a short pause (っ) against a long vowel (う), and it is exactly the kind of difference an English ear lets through. When a date matters, repeat it back with the month: 五月(ごがつ)八日(ようか).

The 20th has a name of its own

Beyond the first ten, one more day keeps an old name: the 20th is 二十日(はつか). The days around it are regular — 十九日(じゅうくにち), 二十一日(にじゅういちにち) — except the 14th and the 24th, which borrow the name of the 4th: 十四日(じゅうよっか), 二十四日(にじゅうよっか).

Year, month, day

A Japanese date runs from the largest unit to the smallest: year, month, day. On a form, a ticket or a letter it is written 2024年(ねん)7月(がつ)23日(にち), with no comma anywhere. A British date, day first, has to be turned round completely; an American one only needs the year moved to the front.

Four yen has a short four

A price is a number with 円(えん) after it, and the only number that changes its sound is four: 四円(よえん), and so 十四円(じゅうよえん) and 二十四円(にじゅうよえん). Four hundred and four thousand keep their よん: 四百円(よんひゃくえん), 四千円(よんせんえん). And the word itself is えん, without the y of the English spelling.

Third in a row, not number three

三番(さんばん) is number three, a label — on a platform sign, a locker, a ticket. 三番目(さんばんめ) is the third in a row, counted from somewhere. English says “third” for both. For a formal series — the third chapter, the third meeting — Japanese puts 第(だい) in front of the number instead: 第三(だいさん).

The decimal point bends the number

A decimal point is read 点(てん), and the digits after it one at a time: 3.14 is 三点一四(さんてんいちよん). The point behaves like a counter, so the number in front of it bends: 一点(いってん), 八点(はってん), 十点(じゅってん). A nought before the point is usually 零(れい): 0.5 is 零点五(れいてんご), and ゼロてんご is heard as well.

The hyphen in a phone number

A phone number is read digit by digit, and each hyphen is read as の, the particle that joins two nouns. Zero is ゼロ (or まる, a circle), four よん, seven なな and nine きゅう — the readings least likely to be misheard. Many people stretch two and five to two beats, にい and ごお, so that every digit takes the same time.