Ethereum Max Fee per Gas vs. Actual Fee
Your wallet’s max fee per gas is the most you’re willing to pay for one unit of gas. Multiply it by the gas limit to get the most you could pay in gas for a regular Ethereum Mainnet transfer. The actual fee uses the gas consumed and the price paid per unit.
A worked example
Say your wallet shows a gas limit of 65,000 and a max fee of 20 gwei. The most you could pay in gas is 0.0013 ETH. If the transfer actually uses 55,000 gas at an effective price of 12 gwei, the fee is 0.00066 ETH.
Open the 65,000 gas example in the calculator or see how to convert gwei to ETH.
Gas limit vs. gas used
Your gas limit is how many units of gas the transaction can use at most. Gas used is how many units Ethereum actually charged for. In the example above, the transfer used 55,000 of the 65,000 units allowed. You only pay for the 55,000 units.
To check what you paid, open the transaction in a block explorer and look for Gas Used and Effective Gas Price. Enter those numbers in the gas calculator to get the fee in ETH.
What if the transaction ran out of gas?
If the whole transaction runs out of gas after it gets into a block, it fails and you still pay for the gas it used. Check the transaction status and look for the failure reason before trying again. If your wallet says “insufficient funds” before sending, check whether you have enough ETH to cover the fee your wallet shows.
Which numbers should I look for?
- Gas limit. The most gas units the transaction can use.
- Max fee per gas. Your price cap per unit, usually shown in gwei. It includes room for the network’s base fee and a tip.
- Gas used and effective gas price. Look for these in the confirmed transaction details to calculate the fee you actually paid.
A wallet can reject a transfer if it can’t cover the upfront cost. If it says you’re short on ETH, see the insufficient gas guide.