How to Write Numbers in Japanese
Japanese numbers can be written in four ways: Arabic numerals (1, 2, 3), kanji (一, 二, 三), hiragana (いち, に, さん), and the formal daiji set used on financial documents (壱, 弐, 参). Each has its place. This page shows which to use when.
The four ways - comparison
| Numeral | Kanji (everyday) | Hiragana | Daiji (formal) |
|---|---|---|---|
| 1 | 一 | いち | 壱 |
| 2 | 二 | に | 弐 |
| 3 | 三 | さん | 参 |
| 4 | 四 | よん | 肆 |
| 5 | 五 | ご | 伍 |
| 6 | 六 | ろく | 陸 |
| 7 | 七 | なな | 漆 |
| 8 | 八 | はち | 捌 |
| 9 | 九 | きゅう | 玖 |
| 10 | 十 | じゅう | 拾 |
| 100 | 百 | ひゃく | 佰 |
| 1000 | 千 | せん | 阡 |
| 10000 | 万 | まん | 萬 |
Arabic numerals (1, 2, 3)
Dominant in modern horizontal Japanese text. Newspapers, websites, business reports, scientific papers, and financial statements all use Arabic numerals. They handle big numbers efficiently and align well in tables. The web is mostly Arabic.
Kanji (一, 二, 三)
Standard in vertical text and traditional contexts: novels, calligraphy, formal letters, poetry, classical literature, some legal documents. Compound kanji numbers follow the spoken pattern: 二十 (20), 三百 (300), 三千 (3000), 一万 (10,000). Note that 一 is dropped before hyaku and sen when standing alone (100 = 百 hyaku, not 一百), but kept before man (一万 ichi-man).
Hiragana (いち, に, さん)
Used in textbooks for early learners, in children’s books, and as furigana over kanji in publications aimed at non-native readers. Hiragana carries the reading directly, so the dual readings of 4, 7, 9 become visible: し or よん. Hiragana is unusual in adult writing for numbers but never wrong.
Daiji - formal financial kanji
Daiji are visually-complex alternatives to the simple kanji, used to prevent forgery on financial documents. The basic 一, 二, 三 can be tampered with by adding strokes (一 plus a stroke becomes 二). The complex daiji forms 壱, 弐, 参 cannot be confused or extended, so they appear on bank cheques, contracts, tax forms, and notarised documents.
The full set: 壱 (1), 弐 (2), 参 (3), 肆 (4), 伍 (5), 陸 (6), 漆 (7), 捌 (8), 玖 (9), 拾 (10), 佰 (100), 阡 (1000), 萬 (10,000). Many of these are technically older or alternate forms; the most common practical set is 壱, 弐, 参, 拾, 萬. Source: Wikipedia "Daiji" entry, Japanese banking templates.
Katakana
Very rare for numbers. Sometimes used in loanword contexts (テン for "ten" in tennis scoring; ナンバー for "number") but not for the underlying numerals. Treat as a curiosity, not a practical script.
Practical advice for learners
Read all four. Write Arabic. Recognise daiji on documents. Practise kanji stroke order if you want to handwrite Japanese; it changes the visual rhythm of your text and makes kanji lookup tools work better.
Frequently asked questions
When do I write numbers in kanji and when in Arabic?
Modern horizontal text (web, newspaper articles, mobile apps, business reports, scientific papers) uses Arabic numerals by default. Vertical text (traditional novels, calligraphy, formal letters, classical poetry) uses kanji. For mixed contexts, follow the dominant convention of the publication.
What is daiji and when do I need it?
Daiji are formal kanji used on financial documents to prevent forgery. The simple kanji 一, 二, 三 can be modified to look like each other (a single horizontal stroke can be added), so banks, contracts, and tax forms use the visually-distinct 壱, 弐, 参. Most learners only need to recognise daiji on documents, not write them actively.
Should I learn to write kanji 1 to 10 by hand?
Yes if you intend to handwrite Japanese, even casually. Stroke order matters because it changes the shape and rhythm of the kanji. Even with digital input, knowing stroke order helps with kanji lookup tools and recognition. Watch out for 4 (五 strokes, not 4) and 5 (4 strokes, not 5).
Why is 一 dropped in compound numbers like 百, 千, 万?
Convention. 100 = hyaku, not ichi-hyaku. 1000 = sen, not ichi-sen. 10,000 keeps the ichi: 一万 (ichi-man). The pattern is "drop ichi- before hyaku and sen when it stands alone, keep it before man and oku always". 11,000 is ichi-man-sen (the ichi attaches to man, not to sen).
Continue: 1 to 10 (with stroke counts) · sources and stroke-order references.