1 # Punycode.js [![Build status](https://travis-ci.org/bestiejs/punycode.js.svg?branch=master)](https://travis-ci.org/bestiejs/punycode.js) [![Code coverage status](http://img.shields.io/coveralls/bestiejs/punycode.js/master.svg)](https://coveralls.io/r/bestiejs/punycode.js) [![Dependency status](https://gemnasium.com/bestiejs/punycode.js.svg)](https://gemnasium.com/bestiejs/punycode.js)
3 A robust Punycode converter that fully complies to [RFC 3492](https://tools.ietf.org/html/rfc3492) and [RFC 5891](https://tools.ietf.org/html/rfc5891), and works on nearly all JavaScript platforms.
5 This JavaScript library is the result of comparing, optimizing and documenting different open-source implementations of the Punycode algorithm:
7 * [The C example code from RFC 3492](https://tools.ietf.org/html/rfc3492#appendix-C)
8 * [`punycode.c` by _Markus W. Scherer_ (IBM)](http://opensource.apple.com/source/ICU/ICU-400.42/icuSources/common/punycode.c)
9 * [`punycode.c` by _Ben Noordhuis_](https://github.com/bnoordhuis/punycode/blob/master/punycode.c)
10 * [JavaScript implementation by _some_](http://stackoverflow.com/questions/183485/can-anyone-recommend-a-good-free-javascript-for-punycode-to-unicode-conversion/301287#301287)
11 * [`punycode.js` by _Ben Noordhuis_](https://github.com/joyent/node/blob/426298c8c1c0d5b5224ac3658c41e7c2a3fe9377/lib/punycode.js) (note: [not fully compliant](https://github.com/joyent/node/issues/2072))
13 This project is [bundled](https://github.com/joyent/node/blob/master/lib/punycode.js) with [Node.js v0.6.2+](https://github.com/joyent/node/compare/975f1930b1...61e796decc) and [io.js v1.0.0+](https://github.com/iojs/io.js/blob/v1.x/lib/punycode.js).
17 Via [npm](https://www.npmjs.com/) (only required for Node.js releases older than v0.6.2):
23 Via [Bower](http://bower.io/):
26 bower install punycode
29 Via [Component](https://github.com/component/component):
32 component install bestiejs/punycode.js
38 <script src="punycode.js"></script>
41 In [Node.js](https://nodejs.org/), [io.js](https://iojs.org/), [Narwhal](http://narwhaljs.org/), and [RingoJS](http://ringojs.org/):
44 var punycode = require('punycode');
47 In [Rhino](http://www.mozilla.org/rhino/):
53 Using an AMD loader like [RequireJS](http://requirejs.org/):
59 'punycode': 'path/to/punycode'
64 console.log(punycode);
71 ### `punycode.decode(string)`
73 Converts a Punycode string of ASCII symbols to a string of Unicode symbols.
76 // decode domain name parts
77 punycode.decode('maana-pta'); // 'mañana'
78 punycode.decode('--dqo34k'); // '☃-⌘'
81 ### `punycode.encode(string)`
83 Converts a string of Unicode symbols to a Punycode string of ASCII symbols.
86 // encode domain name parts
87 punycode.encode('mañana'); // 'maana-pta'
88 punycode.encode('☃-⌘'); // '--dqo34k'
91 ### `punycode.toUnicode(input)`
93 Converts a Punycode string representing a domain name or an email address to Unicode. Only the Punycoded parts of the input will be converted, i.e. it doesn’t matter if you call it on a string that has already been converted to Unicode.
96 // decode domain names
97 punycode.toUnicode('xn--maana-pta.com');
99 punycode.toUnicode('xn----dqo34k.com');
102 // decode email addresses
103 punycode.toUnicode('джумла@xn--p-8sbkgc5ag7bhce.xn--ba-lmcq');
104 // → 'джумла@джpумлатест.bрфa'
107 ### `punycode.toASCII(input)`
109 Converts a lowercased Unicode string representing a domain name or an email address to Punycode. Only the non-ASCII parts of the input will be converted, i.e. it doesn’t matter if you call it with a domain that’s already in ASCII.
112 // encode domain names
113 punycode.toASCII('mañana.com');
114 // → 'xn--maana-pta.com'
115 punycode.toASCII('☃-⌘.com');
116 // → 'xn----dqo34k.com'
118 // encode email addresses
119 punycode.toASCII('джумла@джpумлатест.bрфa');
120 // → 'джумла@xn--p-8sbkgc5ag7bhce.xn--ba-lmcq'
125 #### `punycode.ucs2.decode(string)`
127 Creates an array containing the numeric code point values of each Unicode symbol in the string. While [JavaScript uses UCS-2 internally](https://mathiasbynens.be/notes/javascript-encoding), this function will convert a pair of surrogate halves (each of which UCS-2 exposes as separate characters) into a single code point, matching UTF-16.
130 punycode.ucs2.decode('abc');
131 // → [0x61, 0x62, 0x63]
132 // surrogate pair for U+1D306 TETRAGRAM FOR CENTRE:
133 punycode.ucs2.decode('\uD834\uDF06');
137 #### `punycode.ucs2.encode(codePoints)`
139 Creates a string based on an array of numeric code point values.
142 punycode.ucs2.encode([0x61, 0x62, 0x63]);
144 punycode.ucs2.encode([0x1D306]);
148 ### `punycode.version`
150 A string representing the current Punycode.js version number.
152 ## Unit tests & code coverage
154 After cloning this repository, run `npm install --dev` to install the dependencies needed for Punycode.js development and testing. You may want to install Istanbul _globally_ using `npm install istanbul -g`.
156 Once that’s done, you can run the unit tests in Node using `npm test` or `node tests/tests.js`. To run the tests in Rhino, Ringo, Narwhal, PhantomJS, and web browsers as well, use `grunt test`.
158 To generate the code coverage report, use `grunt cover`.
160 Feel free to fork if you see possible improvements!
164 | [![twitter/mathias](https://gravatar.com/avatar/24e08a9ea84deb17ae121074d0f17125?s=70)](https://twitter.com/mathias "Follow @mathias on Twitter") |
166 | [Mathias Bynens](https://mathiasbynens.be/) |
170 | [![twitter/jdalton](https://gravatar.com/avatar/299a3d891ff1920b69c364d061007043?s=70)](https://twitter.com/jdalton "Follow @jdalton on Twitter") |
172 | [John-David Dalton](http://allyoucanleet.com/) |
176 Punycode.js is available under the [MIT](https://mths.be/mit) license.