Number to Words Converter

How to Use

Type or paste a number in the input field. The tool instantly converts it to three formats: standard English words (e.g. "one thousand two hundred thirty-four"), Japanese kanji numerals (e.g. 千二百三十四), and formal daiji (e.g. 壱阡弐百参拾四 — used on checks, contracts, and receipts in Japan to prevent alteration). Each result has a copy button so you can paste it straight into a document.

What This Tool Does

Converting numbers into words is a common task when writing checks, legal documents, academic papers, or practicing English and Japanese. Each locale has its own conventions — English uses "one thousand" while Japanese mostly omits 一 and writes 千 directly. Daiji (大字) is the Japanese system of complex kanji used on formal financial documents because the simpler digits (一, 二, 三) can be easily altered with a pen stroke.

Supported Range

This tool accepts any integer from −999,999,999,999,999 to +999,999,999,999,999 (below 10^15), and decimals where the fractional part is read digit by digit. Numbers that are too large, non-numeric tokens, or expressions are not accepted — only plain decimal numbers. The English output uses short-scale naming (thousand, million, billion, trillion). The Japanese output uses the myriad system (万, 億, 兆, 京).

Common Use Cases

• Writing a check or invoice where the amount must be spelled out in words.
• Filling out Japanese forms or receipts that require 漢数字 or 大字 representation.
• Academic and legal writing where numbers must appear as words.
• Teaching or learning English/Japanese numerals.
• Accessibility use — screen-reader-friendly rendering of numeric values.

Tips

• Use commas or spaces between words, not hyphens — "forty-two" is the only hyphenated form in English.
• Daiji (壱, 弐, 参, 拾, 阡, 萬) is required on Japanese checks and some contracts because simpler kanji can be forged.
• Decimals are read digit-by-digit after the decimal point (3.14 → "three point one four").
• Negative numbers are prefixed with "negative" in English and マイナス in Japanese.
• For whole-yen amounts on a check, use 金 and 圓 around the daiji (e.g. 金壱阡圓).

Privacy

All conversions happen in your browser. The numbers you enter are never sent to any server or stored anywhere.