Estimate Gas too big

Question

Im trying to estimate the gas of this kind of tx to send to a contract

 var estimateGas = this.web3.eth.estimateGas({
  to: toContractAddress,
  gasPrice: this.web3.toHex(40000000000),
  nonce: 10,
  value: this.web3.toHex(forwardingValueInWei)
})

And I get as return this value: 4 712 388 which is super big gas, while the MyEtherWallet estimate 127 943

are those estimations the same unit? Why is too big from web3?

Answer 1

4,712,388 is the old block gas limit. This used to be the most gas you could send in a transaction. This probably means that your software is detecting an error condition. An error takes all available gas. Since you aren't specifying a limit to how much gas you want to send, this takes all the gas you could possibly send.