Skip to content


Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
A library for parsing and manipulating IPv6 (and v4) addresses in JavaScript
branch: master

Build Status Coverage Status


javascript-ipv6 is a library for manipulating IPv6 addresses in JavaScript.

Pardon our dust

I'm currently working on tearing out the browser-specific stuff because I don't want to duplicate the work of browserify. You should be able to use it just fine with browserify right now but I'd like to do more cleanup before pushing 4.0 to npm.

I'll also be doing some renaming but will keep around the old names with deprecation warnings.


For node:

var v6 = require('ipv6').v6;

var address = new v6.Address('2001:0:ce49:7601:e866:efff:62c3:fffe');

console.log(address.isValid()); // Prints "true"

var teredo = address.teredo();

console.log(teredo.client4);    // Prints ""

Current functionality

  • Parsing of most IPv6 notations
  • Parsing of IPv6 Addresses and Ports from URLs with v6.Address.fromURL(url)
  • Validity checking
  • Decoding of the Teredo information in an address
  • Whether one address is a valid subnet of another
  • What special properties a given address has (multicast prefix, unique local address prefix, etc.)
  • Number of subnets of a certain size in a given address
  • Display methods
    • Hex, binary, and decimal
    • Canonical form
    • Correct form
    • IPv4-compatible (i.e. ::ffff:
  • Works in node.js and the browser
  • Unit tests with node.js and Mocha

Used by

Future functionality

  • Investigate procstreams for the CLI tool
  • Base 64/85 encoding?
  • Reverse lookups? (Whether a domain name has IPv6 glue)


  • Documentation
  • npm deprecate, rename to ip-address
Something went wrong with that request. Please try again.