Ask a beginner to say "two pencils" in Japanese and they will usually try ni enpitsu. It is a reasonable guess and it is wrong. Japanese cannot attach a bare number to a noun — it needs a counter word in between, and the counter changes according to what is being counted. Two pencils, two cats and two cups of coffee use three different words for "two".
This is the point where a lot of learners decide Japanese is being difficult on purpose. It is not, and there is far less to memorise than it first appears.
The ten counters that cover most conversations
The language has several hundred counters. Daily life runs on roughly ten of them.
| Counter | Reading | Used for | Example |
|---|---|---|---|
| 人 | nin / ri | people | 三人 sannin — three people |
| 個 | ko | small generic objects | 五個 goko — five items |
| 本 | hon | long thin things: pens, bottles, trees, umbrellas | 二本 nihon — two bottles |
| 枚 | mai | flat things: paper, shirts, plates, tickets | 三枚 sanmai — three sheets |
| 匹 | hiki | small animals: cats, dogs, fish, insects | 二匹 nihiki — two cats |
| 台 | dai | machines and vehicles | 一台 ichidai — one car |
| 冊 | satsu | bound volumes: books, magazines | 四冊 yonsatsu — four books |
| 杯 | hai | cupfuls and glassfuls | 二杯 nihai — two cups |
| 階 | kai | floors of a building | 三階 sangai — third floor |
| 歳 | sai | years of age | 十歳 jussai — ten years old |
The sound changes are one rule, not thirty exceptions
Here is the part that makes counters look harder than they are. Watch what happens to 本 across the numbers:
| # | 本 (long objects) | 匹 (small animals) | 杯 (cupfuls) |
|---|---|---|---|
| 1 | 一本 ippon | 一匹 ippiki | 一杯 ippai |
| 2 | 二本 nihon | 二匹 nihiki | 二杯 nihai |
| 3 | 三本 sanbon | 三匹 sanbiki | 三杯 sanbai |
| 4 | 四本 yonhon | 四匹 yonhiki | 四杯 yonhai |
| 5 | 五本 gohon | 五匹 gohiki | 五杯 gohai |
| 6 | 六本 roppon | 六匹 roppiki | 六杯 roppai |
| 7 | 七本 nanahon | 七匹 nanahiki | 七杯 nanahai |
| 8 | 八本 happon | 八匹 happiki | 八杯 happai |
| 9 | 九本 kyuuhon | 九匹 kyuuhiki | 九杯 kyuuhai |
| 10 | 十本 juppon | 十匹 juppiki | 十杯 juppai |
The bolded rows are the same rows in all three columns: 1, 3, 6, 8 and 10. That is not a coincidence, and it is not three separate irregular verbs' worth of memorisation. One pattern is doing all the work:
- After 1, 6, 8 and 10 — numbers that end in a doubled consonant — the h hardens to p: ichi + hon becomes ippon, roku + hiki becomes roppiki.
- After 3, which ends in n, the h softens to b: san + hon becomes sanbon.
- Everything else is regular.
Learn the rule, not the table. Once you hear that 1, 6, 8 and 10 harden and 3 softens, you can generate ippon / roppon / happon / juppon and sanbon yourself, and the same instinct will carry to counters you meet later such as 分 (minutes: ippun, sanpun, roppun) and 匹.
人 is the awkward one
The counter for people is irregular exactly twice, at the start, and then settles down:
| # | Japanese | Reading |
|---|---|---|
| 1 | 一人 | hitori (not ichinin) |
| 2 | 二人 | futari (not ninin) |
| 3 | 三人 | sannin |
| 4 | 四人 | yonin (not yonnin) |
| 5 | 五人 | gonin |
| 6 | 六人 | rokunin |
| 7 | 七人 | nananin / shichinin |
| 8 | 八人 | hachinin |
| 9 | 九人 | kyuunin |
| 10 | 十人 | juunin |
Hitori and futari are leftovers from the older native counting system, which is also where hitotsu and futatsu below come from. They are worth memorising on day one because you will hear them constantly — a table for two in a restaurant is futari desu.
The escape hatch: the つ series
When you cannot remember the right counter, Japanese gives you a general-purpose set that works for most concrete objects up to ten. Native speakers reach for it too.
| # | Japanese | Reading |
|---|---|---|
| 1 | 一つ | hitotsu |
| 2 | 二つ | futatsu |
| 3 | 三つ | mittsu |
| 4 | 四つ | yottsu |
| 5 | 五つ | itsutsu |
| 6 | 六つ | muttsu |
| 7 | 七つ | nanatsu |
| 8 | 八つ | yattsu |
| 9 | 九つ | kokonotsu |
| 10 | 十 | too (no つ) |
Point at a pastry in a bakery and say futatsu kudasai and you will get two of them. Nobody will correct you. Above ten the series stops and you fall back to the regular numbers plus a counter.
One more you will meet early
Age uses 歳, with the same hardening you already know — 一歳 issai, 八歳 hassai, 十歳 jussai. But turning twenty has its own word: 二十歳 is read hatachi, not nijussai. It marks the traditional coming of age, and it appears often enough in conversation and fiction that it is worth knowing as a one-off.
How to look a counter up
Counters are where a dictionary earns its keep, because the kanji tells you nothing about which reading is active. Two habits help:
- Look up the noun, not the number. A good entry for 猫 (cat) will tell you it takes 匹. That is the fact you actually need.
- Check the reading, not just the meaning. Seeing 一本 written tells you nothing about whether it is ichihon or ippon. An offline dictionary that shows kana readings settles it in a second, which matters when you are standing in a shop with no signal.
Counters feel like arbitrary cruelty for about a week, and then the sound changes start sounding wrong when you get them wrong — which is the point at which you have actually learned them.
Look up counters offline
The free English-Japanese Dictionary shows readings in kana and romaji, so you can check whether it is ippon or ippiki without a connection. Free on Android and iOS.
Open the dictionary appFrequently asked questions
Do I really have to memorise all the Japanese counters?
No. There are several hundred in the language but everyday conversation runs on about ten. Learn 人 (people), 個 (things), 本 (long objects), 枚 (flat objects) and 匹 (small animals) first, and use the generic つ series whenever you are stuck. Native speakers use つ themselves when the correct counter escapes them or when the object is hard to classify.
Why does 本 sound like hon, pon and bon?
Japanese avoids awkward consonant sequences. After the doubled consonant in ichi and roku the h-sound hardens to p (ippon, roppon), and after the n in san it softens to b (sanbon). The same pattern governs 匹 (ippiki, sanbiki) and 杯 (ippai, sanbai). It is one rule producing what looks like three irregular words.
What is the difference between 二人 futari and 二個 niko?
They count different things. 二人 futari is two people and uses an irregular native-Japanese reading; 二個 niko is two generic objects and uses the regular Sino-Japanese ni. The first two people counters, hitori and futari, are memorised as exceptions — from three onward it becomes regular: sannin, yonin, gonin.