Postal code → address, in kanji, kana and romaji
Every Japanese form starts with 〒. This gives you the address the way you need it — for the form, for the reading, or for the envelope from abroad — without sending the code to anyone.
- Runs entirely in your browser
- Works offline
- No upload
- No sign-up
- No watermark
Loading the tool…
How it works
- Type the 7-digit code (with or without the hyphen).
- Read the address in kanji, kana and romaji; copy the Japanese or the international line.
- Paste a list for a table with CSV, or search by place name in kanji, kana or romaji.
Why nothing is uploaded
Every operation on this page is done by code running inside your browser tab, using the same engine that renders web pages. The file is read from disk into your tab’s memory, transformed there, and written back out as a download. It is never sent anywhere — not to us, not to a third party.
Verify it yourself
- Open your browser’s developer tools (F12) and select the Network tab.
- Load your file and run the tool.
- The only requests you will see fetch the tool’s own code — and, for a few heavy tools, their open-source engine from a public CDN — plus one small page-view ping to loreatec.jp (page address and title, nothing more). None of them carry your file.
Frequently asked questions
Where does the data come from?
From Japan Post’s official postal-code files: the kanji/kana edition (KEN_ALL, UTF-8) and the romaji edition, combined by this site into one compact table with the edition date shown under the tool. Japan Post publishes updates monthly; the copy here is refreshed with the site.
Why does it download 1.9 MB?
That is the whole country — about 124,000 entries — compressed. It is fetched once, kept by your browser, and every lookup after that is local and instant, online or not. The alternative, asking a server for each code, would mean sending your queries somewhere; this site does not do that.
What does “(other addresses in this area)” mean?
Japan Post uses one code per city for addresses not listed individually (以下に掲載がない場合). The town field is empty on purpose; the code is still valid.
How is the international format built?
Town, city, prefecture, code, JAPAN — the order used on mail sent from abroad — from Japan Post’s own romaji edition, with suffixes written as -shi, -ku, -gun, -machi. Building name and room number are yours to add.