Estimating Transaction Fees

Understanding Gas Estimation on GOAT Network

On the GOAT Network, transaction fees are calculated using EIP-1559 standards. This model dynamically adjusts gas prices based on network demand, ensuring fair and efficient fee estimation. The transaction fee consists of:

1. Base Fee: Determined by EIP-1559 dynamically.
2. Priority Fee (Tip): Optional, used to incentivize faster transaction processing.

Steps for Estimating Fees

1. Estimating Gas Usage

• Leverage Gas Estimation Libraries:

  • Use web3.js or ethers.js to estimate the gas required for transaction execution.

  • Example with web3.js:

    const estimateGasUsage = async (transaction) => {
      const gasEstimate = await web3.eth.estimateGas(transaction);
      return gasEstimate;
    };

• Batch Operations with EIP-1559:

  • Batch transactions reduce gas usage per operation. Use this for high-volume transfers or contract interactions.

2. Retrieving Gas Prices

• Dynamic Gas Price Retrieval:

  • Retrieve gas prices (base fee and priority fee) dynamically using the latest network data.

    const getBaseFee = async () => {
      // Get the latest block
      const latestBlock = await web3.eth.getBlock('latest');
     
      // Get the base fee (for EIP-1559 transactions)
      const baseFeePerGas = web3.utils.fromWei(latestBlock.baseFeePerGas.toString(), 'wei')
      return baseFeePerGas;
    };

• Include Priority Fee:

  • Use an additional priority fee for faster confirmations:

    async function getMaxPriorityFee() {
      // Call the eth_maxPriorityFeePerGas method
      const maxPriorityFeeWei = await web3.eth.getMaxPriorityFeePerGas();
      return maxPriorityFeeWei
    }

3. Calculating the Total Fee

• EIP-1559 Fee Formula:

  const estimateTransactionFee = async (transaction) => {
    const gasEstimate = await estimateGasUsage(transaction);
    const baseFeePerGas = await getBaseFee();
   
    const priorityFee = await getMaxPriorityFee();
   
    // the best practice is to use baseFeePerGas * 2 + priorityFeePerGas
    const baseFee = web3.utils.toBN(baseFeePerGas).mul(web3.utils.toBN(2));
    const maxFeePerGas = web3.utils.toBN(baseFee).add(web3.utils.toBN(priorityFee));
   
    const totalFee = web3.utils.toBN(gasEstimate).mul(maxFeePerGas);
    return totalFee;
  };

4. Example Fee Estimation

Single Token Transfer

const gasEstimate = await web3.eth.estimateGas({
  from: senderAddress,
  to: tokenContractAddress,
  data: tokenContract.methods.transfer(recipientAddress, amount).encodeABI(),
});
 
const transaction = {
  from: senderAddress,
  to: tokenContractAddress,
  data: tokenContract.methods.transfer(recipientAddress, amount).encodeABI(),
  gasLimit: gasEstimate,
  maxPriorityFeePerGas: web3.utils.toWei('100000', 'wei'), // Minimal priority fee
};
 
const totalFee = await estimateTransactionFee(transaction);
console.log(`Estimated Fee: ${web3.utils.fromWei(totalFee, 'ether')} ETH`);

Batch Operation Example (EIP-1559 Optimized)

const gasEstimate = await web3.eth.estimateGas({
  from: senderAddress,
  to: tokenContractAddress,
  data: tokenContract.methods.safeBatchTransferFrom(
    senderAddress,
    recipientAddress,
    tokenIds,
    amounts,
    "0x"
  ).encodeABI(),
});
 
const transaction = {
  from: senderAddress,
  to: tokenContractAddress,
  data: tokenContract.methods.safeBatchTransferFrom(
    senderAddress,
    recipientAddress,
    tokenIds,
    amounts,
    "0x"
  ).encodeABI(),
  gasLimit: gasEstimate,
  maxPriorityFeePerGas: web3.utils.toWei('100000', 'wei'), // Minimal priority fee
};
 
const totalFee = await estimateTransactionFee(transaction);
console.log(`Estimated Batch Fee: ${web3.utils.fromWei(totalFee, 'ether')} ETH`);

Best Practices

1. Accurate Gas Estimation:

   • Use tools like ethers.js or web3.js for precise gas predictions.

2. Monitor Base Fee Trends:

   • Keep an eye on network conditions through tools like the GOAT Network Explorer (opens in a new tab).

3. Optimize Batch Transactions:

   • Leverage EIP-1559's efficiency for batch operations to lower costs.

4. Test on Testnet3:

   • Validate your fee estimation logic and transactions on Testnet3 before mainnet deployment.

Additional Resources

• EIP-1559 Standard: You can reference the official EIP-1559 documentation (opens in a new tab)
• GOAT Node: Checkout the current status of the official GOAT node on our Github GOAT Node (opens in a new tab).