- What is the correct English format for a Japanese address?
- International mail and most English-language forms use the reverse of the Japanese order. Start with the most specific element (building name or room, then street number), followed by the town or district, then the city or ward (-ku, -shi, -machi), then the prefecture (Tokyo-to, Osaka-fu, Aichi-ken), and finally "Japan" and the 7-digit postal code. For example: 1-2-3 Jingumae, Shibuya-ku, Tokyo 150-0001, Japan.
- What does 丁目番号 mean and how is it converted?
- 丁目 (chome) is a sub-district block number, 番 (ban) is the block, and 号 (go) is the building lot number. Together they form the Japanese street address. This tool converts them to the Western hyphen notation: 3丁目12番8号 becomes 3-12-8. When written with hyphens in Japanese (3-12-8) they are kept as-is after full-width normalization.
- What are full-width characters and why do they appear in Japanese addresses?
- Japanese text entry traditionally uses double-wide "full-width" versions of Latin letters and numbers — for example １２３ instead of 123, or Ａ棟 instead of A棟. These are different Unicode code points from the standard ASCII characters. Many Japanese address databases and forms store numbers in full-width. This converter uses the Unicode NFKC normalization algorithm to convert all full-width digits, letters, and punctuation to their standard half-width equivalents before further processing.
- How does the zip code lookup work?
- The zip code tab queries the free public zipcloud Japan Post API, which covers all ~130,000 Japanese postal codes from the official Ken_All dataset. The API returns the prefecture, city/ward, and town in both kanji and kana. This tool then converts the kanji result to romaji and formats it in English address order. Note: only the bare zip code is transmitted to the API — no personal data.
- Can I convert a list of addresses at once?
- Yes — use the CSV Batch tab. Upload a CSV file (UTF-8 or Shift-JIS encoding), select which column contains Japanese addresses, and optionally select a zip code column to pre-fill prefecture and city data from the zip lookup. The tool adds an address_en column to every row and lets you download the result as a new CSV file. Processing is done entirely in your browser; no data is uploaded.
- How accurate is the romaji conversion?
- The tool uses a comprehensive kanji-to-romaji table for the ~47 prefectures and ~1,800 major cities and wards in Japan, plus a syllabary table for hiragana and katakana (Modified Hepburn romanization). For district and town names (大字・小字) that are not in the built-in table, the tool outputs the original Japanese text in brackets so you can fill it in manually. Address numbers and building names in kanji numerals (一、二、三…) are also converted to Arabic numerals.