What does the "insufficient funds for gas * price + value" error mean when using the EstimateGas function?

Created by Sourajyoti Gupta, Modified on Thu, 30 Nov 2023 at 07:02 PM by Sourajyoti Gupta

The "insufficient funds for gas * price + value" error typically occurs when there are not enough funds available in a wallet to cover the gas fee required for a transaction. This error message indicates that the wallet's balance is insufficient to pay for both the gas cost and the transaction value.

To estimate the gas required for a transaction before executing it, you can use the following JavaScript script as a general guideline:

const ethers = require("ethers")
require('dotenv').config();
const abi = require('./abi.json')

async function main(){

    const  contractAddress =  process.env.CONTRACTADDRESS 
    const pKey = process.env.PKY
    const rpcURL = process.env.RPC
    const provider = new ethers.JsonRpcProvider(rpcURL)
    const signer = new ethers.Wallet(pKey, provider);
    const contract = new  ethers.Contract(contractAddress,abi,provider)

    const encodeFuncData =    contract.interface.encodeFunctionData("createBlog",["Hello",    "hello","url",true]) // func name and args 
    
    const gasEstimate = await provider.estimateGas({
        from:signer.address,
        to: contract.target,
        data: encodeFuncData,
    
    });
    console.log(gasEstimate,"gasEstimate")
}
main()

This script sets up a connection to an Ethereum node, prepares the transaction data, and then estimates the gas required for the transaction. It's a useful technique to prevent running into "insufficient funds for gas" errors when interacting with the Ethereum blockchain.