Tools for Generating Raw Bitcoin Transactions

To generate a Raw Bitcoin Transaction (Raw Tx), you have several options. Here are some popular tools and methods you can use:

1. Bitcoin Core

Bitcoin Core is the reference implementation of the Bitcoin protocol. It provides a full node and wallet functionality.

Use the createrawtransaction RPC command to create an unsigned raw transaction
Then use signrawtransactionwithwallet to sign it

2. Bitcoin-CLI

Bitcoin-CLI is a command-line interface for Bitcoin Core.

Similar to Bitcoin Core, but used via command line
Commands are the same as in Bitcoin Core

3. Programming Libraries

For developers, there are several libraries available:

bitcoinjs-lib (JavaScript): A popular library for creating and signing Bitcoin transactions in JavaScript
python-bitcoinlib (Python): A Python library for Bitcoin
NBitcoin (.NET): Comprehensive Bitcoin library for the .NET framework

4. Online Tools

There are also online tools available, but be cautious when using these, especially with real transactions:

Coinb.in: An open-source JavaScript Bitcoin wallet generator with advanced tools
Bitcore: A full stack for bitcoin and blockchain-based applications

Warning:

Be extremely careful when using online tools, especially with real private keys or transactions. Always verify the source and security of any tool you use.

5. Hardware Wallets

Many hardware wallets provide functionality to create and sign raw transactions:

Ledger
Trezor
ColdCard

Example Using bitcoinjs-lib

Here's a basic example of how you might create a raw transaction using bitcoinjs-lib:


const bitcoin = require('bitcoinjs-lib')
const network = bitcoin.networks.testnet

const txb = new bitcoin.TransactionBuilder(network)
txb.addInput('INPUT_TRANSACTION_HASH', INPUT_INDEX)
txb.addOutput('OUTPUT_ADDRESS', AMOUNT_IN_SATOSHIS)

const keyPair = bitcoin.ECPair.fromWIF('YOUR_PRIVATE_KEY_WIF', network)
txb.sign(0, keyPair)

const rawTx = txb.build().toHex()
console.log(rawTx)

Note:

This is a simplified example. In a real-world scenario, you'd need to handle things like proper input selection, change addresses, and fee calculation.

Conclusion

The choice of tool depends on your specific needs, technical expertise, and security requirements. For maximum security, consider using Bitcoin Core or a hardware wallet. For development and testing, libraries like bitcoinjs-lib can be very useful. Always prioritize the security of your private keys and verify any transaction details before broadcasting.