How a gas fee is calculated
Every operation has a gas cost. A standard ETH transfer needs 21,000 units, and a token transfer or another smart contract call needs more, because it runs code.
Since the fee market change known as EIP-1559, the price per unit has two parts. The base fee is set by the protocol, moves by at most 12.5% from one block to the next depending on how full blocks are, and is burned. The priority fee is a tip to the validator that includes the transaction.
The total is the units of gas used multiplied by the sum of the base fee and the priority fee. Prices are quoted in gwei, one-billionth of an ETH.
What gas means for a wallet or payment product
Gas makes costs vary with demand: the same withdrawal can cost several times more in a busy hour. A product decides who bears that, by charging a fixed withdrawal fee, passing on the live cost or absorbing it.
An address needs ETH to move tokens. Platforms that give each customer a deposit address either fund those addresses before sweeping them, or use contract designs that let another account pay.
A transaction that fails still pays for the gas it used, and one priced too low can wait unconfirmed until it is replaced.
Gas, network fee or withdrawal fee?
- Network fee
- The general term for what any blockchain charges to process a transaction. Gas is how Ethereum-style networks measure and price it.
- Bitcoin fee
- Priced by the transaction's size in bytes, not by computation, and paid to miners.
- Withdrawal fee
- What a platform charges its customer. It may be more or less than the gas the platform pays.
Where Gas shows up in a platform
Modules that do the work
- Custody & walletsWallets on every major chain, with MPC custody from leading providers or your own keys.
- LedgerThe double-entry book of record behind every balance, fee and transfer.
Platforms that need it
Where it is written
The laws and standards this page's facts come from.
- Ethereum.org, Gas and fees (developer documentation)
- EIP-1559: Fee market change for ETH 1.0 chain (Ethereum Improvement Proposals)
General information, not legal advice: what applies to you depends on your services and your market.