Numbers in Japanese: Two Systems, Counters, and Why 4 Is Avoided

Japanese numbers have a reputation, and it is deserved, but not for the reason people think. The digits are easy and perfectly regular: ten words get you to ninety-nine, with no irregular debris. The difficulty is that Japanese runs two separate counting systems, and that you cannot count objects without attaching a counter chosen by the shape of the thing. Add that 4 and 9 are quietly avoided because they sound like death and suffering, and that big numbers group in ten thousands rather than thousands, and you have a system that is logical but full of trapdoors.

This is the complete reference: the full 1 to 100 table with native audio, both systems, the counters that matter, big numbers to the trillion, ordinals, fractions, dates, and the numbers Japan treats as cursed. Bookmark it and you will not need another page.

The short answer: 1 is いち▶, 10 is じゅう▶, 100 is ひゃく▶, 1000 is せん▶, and 10,000 is まん▶. Now the detail.

Japanese Numbers 1 to 100 (Complete Table)

This is the Sino-Japanese system, the one you use for prices, phone numbers, dates and maths. Tap any number to hear a native voice.

1 to 20

21 to 40

41 to 60

61 to 80

81 to 100

No exceptions on that table. Ten words build everything: 47 is literally four-ten-seven. If you can count to ten, you can already count to ninety-nine, which is not true of English, French or German.

The Second System: Hitotsu, Futatsu

Japanese kept a native counting system alongside the Chinese-derived one, used for counting general objects when no specific counter fits.

It stops at ten. Above that, everyone reverts to juuichi, juuni. Use it for ordering, pointing, counting vague things: ビールを二つください▶, "two beers please". It is your safe fallback when you do not know the correct counter, which is often, and natives will understand you perfectly.

Counters: The Real Difficulty

You cannot say "three cats" with just san. The number needs a counter, chosen by the nature of the object.

The counters change the sound of the number: ichi + hon becomes ippon, not ichihon. Ichi + hiki becomes ippiki. San + hon becomes sanbon. These shifts are mandatory, and they are why Japanese numbers feel harder than they look on paper.

The honest advice: learn hitotsu/futatsu as your escape hatch, add nin, hon, mai and ko next, and pick up the rest as life demands. Nobody learns all two hundred counters.

Big Numbers Group in Four Digits, Not Three

This is the one that ambushes advanced learners. English groups by thousands. Japanese groups by ten thousands, with its own word.

So a salary of ¥3,000,000 is sanbyaku man, "three hundred man". Converting on the fly between the two groupings is a real skill, and it is why fluent speakers still pause on large yen figures.

Watch the sound changes in the hundreds: 300 is さんびゃく▶ (sanbyaku, not sanhyaku), 600 is ろっぴゃく▶ (roppyaku), 800 is はっぴゃく▶ (happyaku). Thousands do it too: 3000 is さんぜん▶ (sanzen), 8000 is はっせん▶ (hassen).

Four and Nine: The Numbers Japan Avoids

Shi (4) is a homophone of 死, death. Ku (9) sounds like 苦, suffering. So in everyday counting Japanese people say よん▶ (yon) and きゅう▶ (kyuu) instead.

This is not folklore you can ignore. It is live daily usage:

• Hospitals skip room 4. Buildings skip floor 4, and sometimes 9 and 13 too.
• Gift sets never contain four items. Giving four of anything reads as a curse.
• Some parking lots have no space 4.
• 42 is especially bad: shi-ni, "to death". 49 is worse: shi-ku, "suffering until death". Car plates avoid both.

But some fixed expressions keep the old readings, and you have to learn which: April is しがつ▶ (shi-gatsu), never yon-gatsu. Seven o'clock is shichi-ji. The rule is: counting freely, use yon and kyuu; inside a fixed compound, the compound wins.

Ordinal Numbers

Japanese builds ordinals by adding 目 (me) after the counter, or 第 (dai) before the number:

一番▶ (ichiban) on its own means "number one", "the best". It is one of the most useful words in the language: ichiban oishii, "the tastiest".

Fractions, Decimals and Percentages

Fractions run backwards to English: nibun no ichi is literally "of two parts, one". You say the denominator first. And the decimal point is てん▶ (ten), from the English "point".

Pronunciation: What the Romaji Hides

Three details do most of the work.

Long vowels are different words. Juu (10) has a held vowel. Ju does not exist. Cutting it short is not an accent, it is a mispronunciation. Same with kyuu (9) and roku versus rokku.

The double consonants in ippon, ippiki, mittsu are real. There is a genuine stop where the small っ sits. English speakers glide over it and lose the word.

Numbers reshape when they meet counters. Ichi + satsu = issatsu. San + hyaku = sanbyaku. Roku + hyaku = roppyaku. Romaji spells the result but never explains it, so learners memorise each combination as a separate word, which is exactly the wrong strategy.

This is exactly where written guides run out of road. Romaji can spell roppyaku, but it cannot put the stop in your mouth or the rhythm in your ear, and a counter you have only ever read is a counter you will fumble at a till. The only fix is to hear a native say the whole phrase, then say it back out loud, several times, until it stops being a calculation. That listen and repeat loop is called shadowing, and it is the fastest way to turn sanbon from a rule you apply into a sound you simply produce. It is how the Hyperpolyglot app handles every phrase: real sentences, native audio, looped until they come out automatically. Available on iOS, Android, and Web.

Dates: The Irregular Corner

Days of the month are the most irregular thing in Japanese numbers. The first ten use native readings and must be memorised:

Tsuitachi (1st) and hatsuka (20th) have nothing to do with ichi or nijuu. They are simply different words. From the 11th on, most dates are regular (juuichinichi), with 14, 20 and 24 as the exceptions.

Months, by contrast, are perfectly regular: ichigatsu (January) through juunigatsu (December). Only April (shigatsu), July (shichigatsu) and September (kugatsu) keep the old readings.

Common Mistakes to Avoid

1. Counting objects with ichi, ni, san alone. Ni biiru is not Japanese. Use biiru wo futatsu or the right counter.
2. Saying shi and ku when counting. Use yon and kyuu, unless the expression is fixed.
3. Saying ichi-hon. It is ippon. The sound change is compulsory.
4. Grouping big numbers by thousands. 10,000 is ichiman, a single unit, not ten of something.
5. Assuming hitotsu goes past ten. It stops at too.
6. Reading 一日 as ichinichi for a date. That means "one day". The 1st of the month is tsuitachi.
7. Giving four of anything as a gift. Culturally loaded. Give three or five.

Bonus: The Numbers You Will Actually Use First

• Ordering: これを二つください▶, "two of these please". This one sentence handles most restaurants.
• Price: いくらですか▶, "how much?"
• People: 二人です▶, "two of us", walking into a restaurant.
• Age: 三十歳です▶, "I'm thirty".
• Phone: read digit by digit, and 0 is ゼロ▶ (zero) or れい▶ (rei).

Learn ichi to juu, learn hitotsu to too as your escape hatch, drill man until big yen figures stop hurting, and add counters as life demands them. Do it with real audio rather than a table, and Japanese numbers stop being a puzzle and start being speech.

Keep Reading

• Language Islands -- the real-sentence method that turns vocabulary into actual conversations
• The Shadowing Technique -- how to drill pronunciation until it becomes automatic
• How to Learn Multiple Languages at the Same Time