🔢 Kanji Numerals Converter (一二三 / 壱弐参)

Japanese writes numbers using kanji numerals (漢数字) that follow a positional system based on powers of ten thousand. The everyday set - 一二三四五六七八九十百千万 - is used in addresses, book chapters, and ordinary text. The formal daiji (大字) set - 壱弐参肆伍陸漆捌玖拾佰阡萬 - is reserved for banknotes, legal contracts, and ceremonial documents because the simpler characters 一, 二, 三 can be altered by adding a single stroke, which made them unsafe on historic financial papers.

This kanji numerals converter turns an Arabic number like 12,345 into 一万二千三百四十五 (standard) or 壱萬弐阡参佰肆拾伍 (banking), and converts the kanji back into digits. It is useful for filling out Japanese bank forms, writing wedding and funeral amounts, localising apps, and checking whether a price on a contract matches the digits. If you also need the kana reading of those characters, the kana converter handles the script side and the kanji reading lookup gives the pronunciation.

Refer to the table below for the digit and unit characters used in both styles:

To go from digits to kanji, the converter splits the number into groups of four digits (because Japanese counts in 万 units of ten thousand, not thousands). Each four-digit group is rendered as [thousands]千[hundreds]百[tens]十[units], with the 一 dropped before 十, 百, and 千 when it equals one (so 100 is 百, not 一百, and 10 is 十, not 一十). Each group is then tagged with its unit suffix - 万, 億, 兆 - and concatenated. The reverse direction parses the kanji string by summing each digit-unit pair, so 百二十三 is read as 100 + 2×10 + 3 = 123, while 千二百 = 1,200.

The table below shows how a few sample numbers decompose under the standard rule:

For the spoken reading of any of these characters, the furigana generator can add kana above the kanji, and the kanji reading lookup lists the on and kun readings. To count digits in the output, paste it into the Japanese character counter.

1. Enter an Arabic number (like 12345) or kanji numerals (like 一万二千三百四十五).
2. Choose the output style - standard (一二三) or banking daiji (壱弐参).
3. Click Convert to see the result in the opposite form.
4. Check the decomposition table to understand how the number was built.
5. Copy the kanji output for use in documents, forms, or localisation.

What is the difference between standard and banking kanji numerals?

Standard numerals (一二三) are for everyday use; banking daiji (壱弐参) are formal characters used on banknotes, contracts, and ceremonial money envelopes because the simple shapes of 一, 二, 三 can be altered by adding strokes, making them unsafe for financial documents.

Why does 100 become just 百 with no 一 in front?

Japanese drops the digit 一 when it is the multiplier of a unit (十, 百, 千) and equals exactly one. So 10 is 十, 100 is 百, 1000 is 千, but 200 is 二百 and 300 is 三百.

What is the largest number this tool can handle?

It supports units up to 兆 (10^12) and 億 (10^8), so it comfortably handles any realistic financial or statistical value. Beyond 兆, results may concatenate multiple 兆 groups.

Can it convert kanji back to Arabic digits?

Yes. The converter parses kanji in both directions - it reads a string like 千二百三十四 and evaluates it as 1234, working for both standard and banking daiji characters.

Does it handle 零 (zero) and decimals?

Zero is written 零 or 〇. Decimals are not traditional in kanji numerals, so the tool focuses on integers; a decimal value is rounded to its integer part for the kanji output.

Why does Japanese use 万 (10,000) instead of a thousand grouping?

Japanese (like Chinese) counts in powers of ten thousand rather than one thousand. That is why there is a single character 万 for 10,000 and 億 for 100,000,000, but no dedicated character for 1,000,000 - that is 百万, "a hundred ten-thousands".

When writing a money amount on a Japanese bank transfer (振込) or an envelope for a wedding (ご祝儀), use the banking daiji style - it is specifically designed to resist forgery, which is why you will see 壱万円 and not 一万円 on official documents. The everyday standard style is fine for prose, addresses, page numbers, and anything non-financial. Remember that Japanese groups by ten thousand, so 12,345 (twelve thousand) is one-万 two-thousand three-hundred forty-five, not "twelve thousand" - this trips up machine translators. The unit 万 is also where Japanese and Western grouping diverge: 1,0000 vs 10,000. Avoid mixing 半 (half) into numbers - it is a word, not a digit. For prices, the 円 (yen) symbol is added after the number, never before.