# bitcoinjs-lib [![Build Status](https://travis-ci.org/bitcoinjs/bitcoinjs-lib.png?branch=master)](https://travis-ci.org/bitcoinjs/bitcoinjs-lib) [![Browser Support](https://ci.testling.com/bitcoinjs/bitcoinjs-lib.png)](https://ci.testling.com/bitcoinjs/bitcoinjs-lib) A pure JavaScript Bitcoin library for node.js and browsers. Backed by (slowly improving) testing, proven by over a million wallet users. The backbone for almost all Bitcoin web wallets in production today. **Warning**: Master is not stable. Expect the interface to change rapidly, including some of the examples below. This is not the original bitcoinjs-lib that was not updated for a while. The current bitcoinjs-lib has been refactored to clean things up, add new functionality and merge improvements from the community. If you are looking for the original, it will be tagged as `0.1.3`. We will use `0.2.x` for releases based on these changes, so be sure to use the `0.1.3` tag if you need the original version. ## Features - Bitcoin Testnet and Mainnet (production) support - [HD Wallets](https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki) - Highly secure random private key / address generation using [window.crypto.getRandomValues](https://developer.mozilla.org/en-US/docs/Web/API/Window.crypto) - ECDSA signing and verification - Transaction creation (pay-to-pubkey-hash), support for multisignature transactions - A (somewhat incomplete) wallet implementation, improvements ongoing ## Installation `npm install bitcoinjs-lib` Note: The npm version is currently out of date, are working to resolve this. The best way to use the latest code is to clone the repository. ## Setup ### Node.js var bitcoin = require('bitcoinjs-lib') From the repo: var bitcoin = require('./src/index.js') ### Browser Compile `bitcoinjs-min.js` with the following command: $ npm run-script compile After loading this file in your browser, you will be able to use the global `Bitcoin` object. ## Usage These examples assume you are running bitcoinjs-lib in the browser. ### Generating a Bitcoin address ```javascript key = new Bitcoin.ECKey() // Print your private key (a hex string) console.log(key.toString()) // => 8c112cf628362ecf4d482f68af2dbb50c8a2cb90d226215de925417aa9336a48 // Print your public key (defaults to a Bitcoin address) console.log(key.getPub().getAddress()) // => 14bZ7YWde4KdRb5YN7GYkToz3EHVCvRxkF ``` ### Creating a Transaction ```javascript tx = new Bitcoin.Transaction() // Add the input (the output of the previous transaction) of the form [previous transaction hash]:[index of the output to use] tx.addInput("aa94ab02c182214f090e99a0d57021caffd0f195a81c24602b1028b130b63e31", 0) // Add the output (who to pay to) of the form [payee's bitcoin address]:[amount in satoshis] tx.addOutput("1Gokm82v6DmtwKEB8AiVhm82hyFSsEvBDK", 15000) // Initialize the private key you created earlier so you can sign the transaction key = new Bitcoin.ECKey("5Jxfda2afuyMw3iaxzAwv6FvAs3XxmjV5y3GPAjZDEhRNJaFG5a") // Sign the first input with your key tx.sign(0, key) // Print transaction serialized as hex. You can push the transaction onto the Bitcoin network manually // here: https://blockchain.info/pushtx console.log(tx.serializeHex()) // => 0100000001313eb630b128102b60241ca895f1d0ffca2170d5a0990e094f2182c102ab94aa000000008a47304402200169f1f844936dc60df54e812345f5dd3e6681fea52e33c25154ad9cc23a330402204381ed8e73d74a95b15f312f33d5a0072c7a12dd6c3294df6e8efbe4aff27426014104e75628573696aed32d7656fb35e9c71ea08eb6492837e13d2662b9a36821d0fff992692fd14d74fdec20fae29128ba12653249cbeef521fc5eba84dde0689f27ffffffff01983a0000000000001976a914ad618cf4333b3b248f9744e8e81db2964d0ae39788ac00000000 ``` ## Projects utilizing bitcoinjs-lib - [Blockchain.info Wallet](http://blockchain.info/wallet) - [Bitaddress.org](https://www.bitaddress.org) - [Coinpunk](https://coinpunk.com) - [DarkWallet](https://darkwallet.unsystem.net) - [GreenAddress](https://greenaddress.it) Feel free to send pull requests to have your project/startup listed here. ## Contributing ### Instructions 1. Fork the repo 2. Push changes to your fork 3. Create a pull request ### Running the test suite $ npm test ## Alternatives - [Bitcore](https://github.com/bitpay/bitcore) - [Cryptocoin](https://github.com/cryptocoinjs/cryptocoin) ## License This library is free and open-source software released under the MIT license. ## Copyright BitcoinJS (c) 2011-2012 Stefan Thomas Released under MIT license http://bitcoinjs.org/ JSBN (c) 2003-2005 Tom Wu Released under BSD license http://www-cs-students.stanford.edu/~tjw/jsbn/ CryptoJS (c) 2009–2012 by Jeff Mott Released under New BSD license http://code.google.com/p/crypto-js/