Japan Prefecture Code Lookup

• JIS X 0401: To−Do−Fu−Ken (Prefecture) Identification Code
• Reverse Geocoding: Japan Integrated Grid Square (10km accuracy)
• Standalone: jp-pref-lookup.min.js is just 20KB minified, 6KB gzipped

SYNOPSIS

import {Pref} from "jp-pref-lookup";

// by pair of latitude and longitude
console.log(Pref.lookup({lat: 35.68944, lng: 139.69167})); // => ["13"]

// by comma separated latitude and longitude
console.log(Pref.lookup({ll: "35.3606,138.7278"})); // => ["22", "19"]

// name for prefecture code
console.log(Pref.name("13")); // => "東京都"
console.log(Pref.name(27)); // => "大阪府"

// prefecture code for name
console.log(Pref.code("東京都")); // => "13"
console.log(Pref.code("大阪")); // => "27"

See TypeScript declaration jp-pref-lookup.d.ts for detail.

CJS

• Both ES Modules and CommonJS supported.

const {Pref} = require("jp-pref-lookup");

WEB BROWSERS

• The minified build of the library is also available for Web browsers via jsDelivr CDN.
• https://cdn.jsdelivr.net/npm/jp-pref-lookup/dist/jp-pref-lookup.min.js
• Here is a sample to works with Geolocation API on Web browsers.

<script src="https://cdn.jsdelivr.net/npm/jp-pref-lookup/dist/jp-pref-lookup.min.js"></script>
<script>
  navigator.geolocation.getCurrentPosition(function(position) {
    var ll = position.coords.latitude + "," + position.coords.longitude;
    var array = Pref.lookup({ll: ll});
    var name = array && Pref.name(array[0]);
    alert(name);
  });
</script>

REFERENCE

• 出典：「市区町村別メッシュ・コード一覧」（総務省統計局） licensed under CC BY 4.0
• https://www.stat.go.jp/data/mesh/m_itiran.html
• https://www.stat.go.jp/english/data/mesh/05-1s.html
• https://github.com/jp-mirror/jp-data-mesh-csv

LINKS

• https://github.com/kawanet/jp-pref-lookup
• https://kikakurui.com/x0/X0401-1973-01.html
• https://www.npmjs.com/package/jp-pref-lookup
• https://www.npmjs.com/package/jp-city-lookup
• https://www.npmjs.com/package/jp-zipcode-lookup

MIT LICENSE

Copyright (c) 2018-2023 Yusuke Kawasaki

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.