Description

Returns an estimate of the amount of gas that would be required to submit a transaction to the network.

An estimate may not be accurate since there could be another transaction on the network that was not accounted for, but after being mined affects the relevant state.

Parameters

transaction object parameters

Response

Example Request and Response

Prerequisite: You will need to install the Alchemy SDK before making requests with it.

The commands for installing it using npm or yarn are given below:

npm install alchemy-sdk@latest

yarn add alchemy-sdk@latest

Request

Here is an example of how to make an estimateGas request using the Alchemy SDK:

// Imports the Alchemy SDK
const { Alchemy, Network, Utils } = require("alchemy-sdk");

// Configures the Alchemy SDK
const config = {
    apiKey: "alchemy-replit", // Replace with your API key
    network: Network.ETH_MAINNET, // Replace with your network
};

// Creates an Alchemy object instance with the config to use for making requests
const alchemy = new Alchemy(config);

const main = async () => {
    //Define the params object
    const params = {
        // Wrapped ETH address
        to: "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
        // `function deposit() payable`
        data: "0xd0e30db0",
        // 1 ether
        value: Utils.parseEther("1.0"),
    };

    //The response returns the block number of the most recently mined block
    let response = await alchemy.transact.estimateGas(params)

    //Logging the response to the console
    console.log(response)
};

main();

Response

{
    "type": "BigNumber",
    "hex": "0x6d22"
}

Code Sandbox

You can test out the estimateGas method using the code sandbox below:

Use Cases

Here are some common use cases for the estimateGas method:

• Optimizing transaction fees: Gas is the fee paid by the sender of a transaction to compensate the miners for processing it. By estimating the gas required for a transaction beforehand, developers can optimize their transaction fees by choosing the right gas price and limit.

• Ensuring successful transactions: If a transaction runs out of gas before it is completed, it will fail and the sender will lose the gas spent on it. By estimating the required gas beforehand, developers can ensure that the transaction has enough gas to complete successfully.

• Validating transaction parameters: When submitting a transaction, certain parameters such as the gas limit and gas price must be set correctly to avoid issues such as network congestion or excessive fees. By using estimateGas, developers can validate these parameters before submitting the transaction.

Related Methods

Here are the methods related to estimateGas:

• getTransaction: Returns the transaction details.
• getMaxPriorityFeePerGas: Returns a fee per gas (in wei) that is an estimate of how much you can pay as a priority fee, or "tip", to get a transaction included in the current block.