Is my input uploaded?

No. The conversion is table lookup plus BigInt integer arithmetic in your browser; nothing is sent anywhere.

What is the difference between place-value, positional, and daiji?

Place-value uses markers like 十・百・千・万 (1234 → 千二百三十四). Positional writes one kanji per digit with 〇 for zero (2026 → 二〇二六). Daiji uses 壱・弐・参・拾, a tamper-resistant style used for amounts on contracts, promissory notes, and official registers.

Which characters does daiji use?

We follow the legally defined set (one/two/three/ten → 壱/弐/参/拾) and output 万 as 萬, leaving four–nine, 百, and 千 as ordinary kanji. When reading input, older variants such as 阡・仟・佰・萬・肆・伍 are also recognized.

How large a number is supported?

Integers below 10^24, covering the 万・億・兆・京・垓 (10^20) places. BigInt is used internally so there is no overflow. Larger values return an error.

Are full-width digits or commas accepted?

Yes. For Arabic → kanji, full-width digits (１２３４) are normalized to half-width and thousands commas, spaces, and underscores are stripped before conversion.

Can I convert decimals or negatives?

No. The tool handles non-negative integers only; values with a decimal point or sign return an error.

Back to Japanese

Kanji Numeral Converter

Convert between kanji numerals and Arabic digits. Supports place-value form (千二百三十四), daiji (壱弐参拾 — the tamper-resistant form used on contracts and promissory notes), and positional form (二〇二六). Handles up to 垓 (10^20), recognizes daiji, full-width digits, and thousands commas. Runs entirely in your browser — no uploads.

japaneseconversiontext

How to use

Pick a direction with "Direction" ("Kanji → Arabic" or "Arabic → Kanji"). When converting to kanji, choose place-value, daiji, or positional under "Kanji style", enter a value, and hit Run. The kanji side reads place-value (千二百三十四), daiji (壱弐参拾), and positional (一二三四) forms. The Arabic side normalizes full-width digits and thousands commas automatically. Everything runs in your browser — no uploads.

FAQ

Is my input uploaded?: No. The conversion is table lookup plus BigInt integer arithmetic in your browser; nothing is sent anywhere.
What is the difference between place-value, positional, and daiji?: Place-value uses markers like 十・百・千・万 (1234 → 千二百三十四). Positional writes one kanji per digit with 〇 for zero (2026 → 二〇二六). Daiji uses 壱・弐・参・拾, a tamper-resistant style used for amounts on contracts, promissory notes, and official registers.
Which characters does daiji use?: We follow the legally defined set (one/two/three/ten → 壱/弐/参/拾) and output 万 as 萬, leaving four–nine, 百, and 千 as ordinary kanji. When reading input, older variants such as 阡・仟・佰・萬・肆・伍 are also recognized.
How large a number is supported?: Integers below 10^24, covering the 万・億・兆・京・垓 (10^20) places. BigInt is used internally so there is no overflow. Larger values return an error.
Are full-width digits or commas accepted?: Yes. For Arabic → kanji, full-width digits (１２３４) are normalized to half-width and thousands commas, spaces, and underscores are stripped before conversion.
Can I convert decimals or negatives?: No. The tool handles non-negative integers only; values with a decimal point or sign return an error.

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