Arabic → Kanji Number Converter

Japanese Kanji numerals (漢数字) are largely derived from Chinese, so they look very similar. Key differences include: Japanese often omits the leading "一" before 十 (10 = 十, not 一十), 百 (100 = 百), and 千 (1000 = 千). Also, Japanese uses 万 (man) for 10,000 and 億 (oku) for 100,000,000 — grouping numbers in units of 4 digits rather than the Western 3-digit grouping. Some readings differ due to kun'yomi vs on'yomi pronunciation layers.

Zero is written as 零 (rei) in formal contexts, or more commonly as 〇 (maru) in everyday use — especially for phone numbers, room numbers, or when reading digits one by one. In this converter, we use 零 for standalone zero. When zero appears in the middle of a number (like 101), it is simply omitted in the Kanji representation (101 = 百一), which is the natural Japanese counting style.

The number 4 (四) can be read as shi, which is a homophone for 死 (death). Similarly, 9 (九) can be read as ku, a homophone for 苦 (suffering/hardship). Because of this, hospitals, hotels, and some buildings often skip the 4th and 9th floors or room numbers. In counting, alternative readings are preferred: yon for 4 and kyū or nana for 7 (to avoid shichi). However, the Kanji characters themselves remain the same regardless of pronunciation.

This converter handles numbers up to 9,999,999,999,999 (approximately 10 trillion / 10兆). This covers 兆 (chō, 10¹²), 億 (oku, 10⁸), 万 (man, 10⁴), and all smaller units. Beyond this range, JavaScript's integer precision may become unreliable. For most practical purposes — including financial amounts, population figures, and everyday large numbers — this range is more than sufficient.

Decimals in Japanese Kanji are expressed using the interpunct ・ (nakaguro) as the decimal separator, followed by each digit read individually. For example, 3.14 becomes 三・一四 (san ten ichi yon). This is different from the Western decimal point "." but serves the same function. In formal mathematical writing, the period "." is also sometimes used, but ・ is more traditional and distinctively Japanese.

Yes! While Arabic numerals (1, 2, 3) are widely used in Japan for most daily purposes — prices, dates, math, and digital displays — Kanji numbers are still common in formal documents, calligraphy, legal papers, restaurant menus, traditional signage, and vertical writing (tategaki). They also appear on Japanese banknotes and in ceremonial contexts. Learning to read Kanji numbers is essential for navigating Japanese culture and understanding traditional texts.