Sending entire ether balance to another wallet

Question

I found the same question but it was asked over 4 years ago but it doesn't seem to work anymore?

How do I send the entire ether balance from one account to another account?

const Web3 = require('web3')
require('dotenv').config()
async function main() {
    const { RPC_URL, PRIVATE_KEY, TO } = process.env;
const web3 = new Web3(new Web3.providers.HttpProvider(RPC_URL))
const pubkey = await web3.eth.accounts.privateKeyToAccount(PRIVATE_KEY).address;

const balance = await web3.eth.getBalance(pubkey);

const currentGas = await web3.eth.getGasPrice();
const requiredGasPrice = await web3.eth.estimateGas({to: TO});
const gas = currentGas * requiredGasPrice;

const nonce = await web3.eth.getTransactionCount(pubkey, 'latest');

const transaction = {
    'to': TO,
    'value': balance - gas,
    'gas': requiredGasPrice,
    'gasPrice': currentGas,
    'nonce': nonce
};    

const signedTx = await web3.eth.accounts.signTransaction(transaction, PRIVATE_KEY);

web3.eth.sendSignedTransaction(signedTx.rawTransaction, function (error, hash) {
    if (!error) {
        console.log(" The hash of your transaction is: ", hash);
    } else {
        console.log("❗ Something went wrong while submitting your transaction: ", error)
    }
});

}
main();

I can't seem to be able to calculate the gas so that it will be able to send all the ether from the wallet.

What do I calculate the gas for the transaction to send funds.

Answer 1

Use the estimateGas method to calculate the gas.

web3.eth.estimateGas

Answer 2

In addition to the answer above I will add that you can calculate the fee needed for the transaction to execute by taking the gas which is needed for simple ether transfer 21000 and multiply it by the current gas price await web3.eth.getGasPrice():

const currentGas = await web3.eth.getGasPrice();
const requiredGasPrice = await web3.eth.estimateGas({to: TO});
const gas = currentGas * requiredGasPrice;

And then pass the gasPrice variable to the transaction object:

const transaction = {
    'to': TO,
    'value': balance - gas,
    'gas': requiredGasPrice,
    'gasPrice': currentGas,
    'nonce': nonce
};

You can also add condition to check if balance is greater than gas. This way you will know this particular wallet will have the enough balance to cover the transaction fee.