Converting Bech32 Bitcoin Addresses to Legacy Format Using Web3.js
When working with Bitcoin, it is not uncommon for developers and users to need to switch between different formats. One such conversion is from the new Bech32 Bitcoin address format used by the Ethereum blockchain (Bech32) to its legacy counterpart, the Segwit Bitcoin address format. In this article, we will explore how you can accomplish this conversion using the popular JavaScript library Web3.js.
Background
Before we dive into the conversion process, let’s quickly recap the differences between Bech32 and Segwit addresses:
- Bech32: A two-part address format that combines a hexadecimal key (public key) with a label (version). It is used by Bitcoin Core wallets and many other applications.
- Segwit: An improvement to the Bech32 format, which splits data into smaller chunks called “tags” and adds support for multiple signatures per block.
Converting Bech32 Addresses to Legacy Segwit Addresses
To convert a native Bech32 Bitcoin address to a legacy Segwit format, you will need to follow these steps:
- Extract the public key (hexadecimal string): Find the hexadecimal representation of the first 34 characters in your Bech32 address. This will be used as the public key for the new address.
- Calculate the block number and timestamp: Use the Web3.js
eth_blockNumberandeth_timestampfunctions to get the current block number and timestamp, respectively. These values can be retrieved using a network provider such as Infura or a local blockchain API (e.g. the Bitcoin Core wallet).
- Create a new Segwit address: Construct a new Segwit address using the following format:
( ) ( ) (<...>)
Here is some sample code to get you started:
const Web3 = require('web3');
const web3 = new Web3(new Web3.providers.HttpProvider('
// Extract the public key (hex string) from the Bech32 address
const bech32Address = '12345678901234567890abcdef';
const publicKey = web3.eth.accounts.fromRawAddress(bech32Address, 0);
// Calculate block number and timestamp
const blockNumber = web3.eth.blockNumber;
const timestamp = web3.eth.timestamp();
// Create a new Segwit address
const segwitAddress = ${blockNumber}${timestamp}${publicKey.toString(16)} (${1}) (${2}) (${3}) (${4}) (${5}) (${6}) (${7});
console.log(segwitAddress);
Note:
The 1, 2, 3, …, 7 in the Segwit address are placeholders for additional signatures, which can be generated using the Ethereum wallet or a standalone service. Be sure to replace these placeholders with the actual values.
This code snippet demonstrates how to extract the public key from a Bech32 address, calculate the block number and timestamp, create a new Segwit address, and print the result. By following this process, you should be able to successfully convert native Bech32 Bitcoin addresses to legacy Segwit formats using Web3.js.
Additional Tips:
- When working with Bitcoin, it is essential to keep in mind that some services may require additional setup or configuration to use Bech32 addresses.
- The Ethereum blockchain has a limited number of blocks per second (around 15), which can impact performance. You may need to adjust your code accordingly.
- Always refer to the official Web3.js documentation and other reliable sources for up-to-date information on the latest changes and best practices.
By following this article, you should now be able to convert Bech32 Bitcoin addresses to legacy Segwit formats using Web3.js. If you have any further questions or need additional help, please feel free to ask!