Japanese Number Converter

The Japanese number system is based on powers of ten, similar to English, but groups digits in units of ten-thousand (man) rather than thousand. The basic digits 1 through 10 each have their own word. Numbers 11 through 99 are formed by combining the tens digit with juu (ten) and the ones digit. For example, 25 is ni-juu go (two-tens five). Larger numbers use hyaku (hundred), sen (thousand), man (ten-thousand), and oku (hundred-million). Several combinations produce irregular sound changes, such as sanbyaku for 300 and hassen for 8000.

Japanese numbers have several irregular readings caused by phonetic sound changes (rendaku). For hundreds: 300 is sanbyaku (not sanhyaku), 600 is roppyaku (not rokuhyaku), and 800 is happyaku (not hachihyaku). For thousands: 3000 is sanzen (not sansen), and 8000 is hassen (not hachisen). These irregular readings are essential to learn for natural-sounding Japanese and are tested on the JLPT N5 exam.

Japanese counters (josushi) are special suffixes added after numbers when counting specific types of objects. Different counters are used for different categories: nin (人) for people, ko (個) for small objects, mai (枚) for flat objects like paper and plates, and hon (本) for long cylindrical objects like pens and bottles. Some counters cause the number pronunciation to change. For example, with the counter hon, 1 becomes ippon, 3 becomes sanbon, and 6 becomes roppon.

Counting people in Japanese uses the counter nin (人), but the first two numbers are completely irregular. One person is hitori (一人), and two people is futari (二人). From three onward, the pattern becomes regular: sannin (三人), yonin (四人), gonin (五人), rokunin (六人), shichinin or nananin (七人), hachinin (八人), kyuunin (九人), and juunin (十人). The words hitori and futari are native Japanese (wago) readings, while the rest use Sino-Japanese (ongo) readings.

Yes, Japanese numbers are a fundamental part of the JLPT N5 curriculum. You are expected to know numbers from 1 to 10,000, including all irregular readings for hundreds and thousands. You also need to know common counters such as nin for people, mai for flat objects, hon for long objects, and ko for small objects. Number-related questions appear in the vocabulary, listening, and reading sections of the exam. Mastering numbers early provides a strong foundation for telling time, dates, prices, and quantities in Japanese.