Having trouble figuring out EIP-1599 params for contract transaction in ethers.js

Question

I am following contracts documentation at https://docs.ethers.io/v5/api/contract/contract/#contract-functionsSend

And got to the point where my contract call looks something like this (someMethod and someArgument are irrelevant placeholder values)

      contract.someMethod(someArgument, {
        gasLimit: 100000,
        maxPriorityFeePerGas: 5,
        maxFeePerGas: 200,
        value: 0.7
      })

Executing this method I am getting all sorts of errors like

underflow

processing response error

I'm not sure why I am getting these, but I think its due to my options that I pass to the contract, they might be in the wrong format? I tried to find docs on how to format these correctly, but had no success. At the moment I am following same input format as in MetaMask extension

Answer 1

The values maxPriorityFeePerGas, maxFeePerGas and value should be in Wei (the smallest unit on Ethereum). You can use Ethers.js' parseUnits to convert a value in Gwei or Ether to Wei:

contract.someMethod(someArgument, {
  gasLimit: 100000,
  maxPriorityFeePerGas: ethers.utils.parseUnits('5', 'gwei'),
  maxFeePerGas: ethers.utils.parseUnits('200', 'gwei'),
  value: ethers.utils.parseUnits('0.7') // 'ether' is the default
});