Node.js v4.1.1 Documentation


Stability: 2 - Stable

Punycode.js is bundled with Node.js v0.6.2+. Use require('punycode') to access it. (To use it with other Node.js versions, use npm to install the punycode module first.)


Converts a Punycode string of ASCII-only symbols to a string of Unicode symbols.

// decode domain name parts
punycode.decode('maana-pta'); // 'mañana'
punycode.decode('--dqo34k'); // '☃-⌘'


Converts a string of Unicode symbols to a Punycode string of ASCII-only symbols.

// encode domain name parts
punycode.encode('mañana'); // 'maana-pta'
punycode.encode('☃-⌘'); // '--dqo34k'


Converts a Punycode string representing a domain name to Unicode. Only the Punycoded parts of the domain name will be converted, i.e. it doesn't matter if you call it on a string that has already been converted to Unicode.

// decode domain names
punycode.toUnicode(''); // 'mañ'
punycode.toUnicode(''); // '☃-⌘.com'


Converts a Unicode string representing a domain name to Punycode. Only the non-ASCII parts of the domain name will be converted, i.e. it doesn't matter if you call it with a domain that's already in ASCII.

// encode domain names
punycode.toASCII('mañ'); // ''
punycode.toASCII('☃-⌘.com'); // ''



Creates an array containing the numeric code point values of each Unicode symbol in the string. While JavaScript uses UCS-2 internally, 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.

punycode.ucs2.decode('abc'); // [0x61, 0x62, 0x63]
// surrogate pair for U+1D306 tetragram for centre:
punycode.ucs2.decode('\uD834\uDF06'); // [0x1D306]


Creates a string based on an array of numeric code point values.

punycode.ucs2.encode([0x61, 0x62, 0x63]); // 'abc'
punycode.ucs2.encode([0x1D306]); // '\uD834\uDF06'


A string representing the current Punycode.js version number.