Docs

eth_estimateGas - MegaETH RPC Method

Estimate gas required for transactions on MegaETH. Essential for optimizing transaction costs for high-frequency trading, real-time gaming, instant payments, and latency-sensitive applications.

Estimates the gas necessary to execute a transaction on MegaETH.

Why MegaETH? Build on the first real-time blockchain with sub-millisecond latency and 100,000+ TPS with sub-millisecond transaction streaming with 100,000+ sustained TPS and full EVM compatibility.

When to Use This Method

The eth_estimateGas method serves these key scenarios for high-frequency DeFi developers, gaming studios, and teams building real-time applications:

  • Calculate gas budgets - Determine how much gas a transaction requires before submitting, helping set accurate gas limits for high-frequency trading, real-time gaming, instant payments, and latency-sensitive applications
  • Estimate costs for complex interactions - Predict gas requirements for multi-step contract calls, such as DeFi composability chains across multiple protocols
  • Compare gas efficiency - Evaluate gas consumption between different contract implementations to identify the most cost-effective approach on MegaETH
  • Prevent out-of-gas failures - Verify that the gas limit is sufficient for the intended transaction to avoid wasted gas on reverted transactions

Common Use Cases

1. Estimate Gas for an ERC20 Transfer

Before sending an ERC20 transfer, estimate the gas cost to ensure you set a sufficient limit. Token transfers typically consume more gas than native ETH transfers because they execute contract logic - most ERC20 implementations use around 45,000-65,000 gas per transfer.

JavaScript
import { JsonRpcProvider, Contract } from 'ethers';

const provider = new JsonRpcProvider('https://api-megaeth-mainnet.n.dwellir.com/YOUR_API_KEY');

const erc20Abi = [
  'function transfer(address to, uint256 amount) returns (bool)'
];
const tokenContract = new Contract('0x0E0f4Dd25ae8AB20E1583D9E8EDFf319A88e1d3f', erc20Abi, provider);

async function estimateTransferGas(to, amount) {
  const gasEstimate = await tokenContract.transfer.estimateGas(to, amount);
  console.log('Estimated gas for transfer:', gasEstimate.toString());
  return gasEstimate;
}

const gas = await estimateTransferGas('0x0E0f4Dd25ae8AB20E1583D9E8EDFf319A88e1d3f', '1000000000000000000');

2. Simulate Contract Deployment Cost

Estimate how much gas a contract deployment will consume before submitting the creation transaction. The deployment cost depends on the bytecode size and constructor arguments - use this to budget for contract deployments on MegaETH.

JavaScript
import { JsonRpcProvider, ContractFactory } from 'ethers';

const provider = new JsonRpcProvider('https://api-megaeth-mainnet.n.dwellir.com/YOUR_API_KEY');

async function estimateDeploymentGas(bytecode, abi, constructorArgs) {
  const factory = new ContractFactory(abi, bytecode, provider);
  const deployTx = await factory.getDeployTransaction(...constructorArgs);
  const gasEstimate = await provider.estimateGas(deployTx);
  console.log('Estimated deployment gas:', gasEstimate.toString());
  return gasEstimate;
}

const estimatedGas = await estimateDeploymentGas(
  '0x608060...',
  ['constructor(uint256)'],
  [42]
);

3. Build Transaction with Gas Buffer

Apply a safety buffer to the estimated gas to account for minor state changes between estimation and execution. The recommended buffer varies by chain - fast, low-congestion chains like MegaETH may need only 20%, while complex DeFi interactions benefit from 50%.

JavaScript
import { JsonRpcProvider, parseEther } from 'ethers';

const provider = new JsonRpcProvider('https://api-megaeth-mainnet.n.dwellir.com/YOUR_API_KEY');

async function buildSafeTransaction(from, to, value, contractData) {
  const [nonce, feeData] = await Promise.all([
    provider.getTransactionCount(from),
    provider.getFeeData()
  ]);

  const tx = {
    from,
    to,
    value: parseEther(value),
    data: contractData || '0x',
    nonce,
    maxFeePerGas: feeData.maxFeePerGas,
    maxPriorityFeePerGas: feeData.maxPriorityFeePerGas
  };

  const estimatedGas = await provider.estimateGas(tx);
  const bufferRatio = contractData ? 1.5 : 1.2;
  tx.gasLimit = BigInt(Math.floor(Number(estimatedGas) * bufferRatio));

  console.log('Estimated gas:', estimatedGas.toString());
  console.log('Buffered gas limit:', tx.gasLimit.toString());
  return tx;
}

const tx = await buildSafeTransaction(
  '0x0E0f4Dd25ae8AB20E1583D9E8EDFf319A88e1d3f',
  '0x0E0f4Dd25ae8AB20E1583D9E8EDFf319A88e1d3f',
  '0.01'
);

Gas Limit Restriction

Gas Limit on MegaETH

On MegaETH, eth_estimateGas requests are subject to a maximum gas limit of 10,000,000. Complex transactions exceeding this limit should be optimized or restructured.

For transactions requiring more than 10M gas:

JavaScript
// Split complex operations into multiple transactions
const operation1 = await contract.step1();
await operation1.wait();

const operation2 = await contract.step2();
await operation2.wait();

Best Practices

  • Add a 20-50% buffer to the estimated gas value for safety: simple transfers need less buffer, complex contract calls need more
  • If the estimate reverts, the transaction would also revert: fix the underlying issue rather than increasing gas
  • eth_estimateGas runs against the current state at block latest: state changes between estimation and execution can alter the actual gas requirement
  • For EIP-1559 chains, combine eth_estimateGas with eth_feeHistory to calculate the accurate total transaction cost in native currency
  • L2 chains may return significantly different gas estimates than L1 for the same contract interaction

Code Examples

Error Handling

Error CodeMessageDescription
-32000Execution revertedTransaction would fail
-32602Invalid paramsInvalid transaction parameters

Tip: If estimation fails, the transaction would likely revert if sent.