Gas Fees Development Tutorials, Guides & Insights

• API: This script uses Infura’s node access and Ethers.js to send Ether in real-time.
• Use Case: Essential for dApps, wallets, or any application needing to send transactions or interact with the blockchain live.

• Data Analytics: Use Etherscan if you need to fetch historical data, such as transaction histories, token balances, or account balances.
• Blockchain Explorers: Ideal for building tools similar to Etherscan itself, where you query and display blockchain data to users.
• Read-Only Data: You can’t send transactions, but you can retrieve information about any Ethereum address, smart contract, or token transfer.

const ethers = require('ethers');

// Replace with your Infura Project ID
const infuraProvider = new ethers.JsonRpcProvider('https://mainnet.infura.io/v3/YOUR_INFURA_PROJECT_ID');

// Replace with the ERC-20 contract address (e.g., USDT, DAI, or any token)
const contractAddress = '0xTokenContractAddress';

// Replace with the wallet address to query the balance
const walletAddress = '0xYourWalletAddress';

// ABI of the ERC-20 token (we only need the balanceOf function here)
const abi = [
    'function balanceOf(address owner) view returns (uint256)'
];

// Create a contract instance
const contract = new ethers.Contract(contractAddress, abi, infuraProvider);

async function getTokenBalance() {
    try {
        // Call the balanceOf function
        const balance = await contract.balanceOf(walletAddress);

        // Convert the balance from wei (for ERC-20 tokens, it could be small denominations)
        console.log(`Token Balance: ${balance.toString()}`);
    } catch (error) {
        console.error('Error fetching token balance:', error);
    }
}

// Call the function to query the token balance
getTokenBalance();

• Contract Address: Replace '0xTokenContractAddress' with the ERC-20 token contract’s address (for example, USDT, DAI, etc.).
• Wallet Address: Replace '0xYourWalletAddress' with the wallet address whose balance you want to query.
• ABI (Application Binary Interface): The ABI specifies the functions and data structures used in the smart contract. In this case, we’re using a simple balanceOf function to query the balance.