Available fee parameters
The following fee parameters are available for all transactions. However, only some parameters are necessary for each transaction depending on the blockchain.
Account-based fee parameters
All transactions
- feeLevel (LOW / MEDIUM / HIGH): For Ethereum only. This is the same as the tentative fee in the Console. Fireblocks uses the 12 most recent blocks to calculate fees, which vary based on the selected transaction speed. Learn more about how preset fees are calculated.
- maxFee (gwei): The maximum fee that should be paid for the transaction. Only set if requested.
- gasLimit* (gas): For EVM only. Units of gas required to process the transaction.
- networkFee* (Ether or equivalent): The total transaction fee in the blockchain's largest unit.
EIP-1559 transactions
- priorityFee (gwei): The maximum allowed priority fee as defined in EIP-1559. The priorityFee is automatically calculated based on the selected preset fee. If no preset fee is selected, the preset fee for medium transaction speed is used by default.
- maxFee (maxFeePerGas): The maximum value an initiator is willing to pay per gas unit. This includes both the baseBlockFee and priorityFee. The transaction sender is refunded the difference between the max fee and the sum of the base fee and tip. You can submit transactions with a maxFeePerGas corresponding to how much you are willing to pay for the transaction to be executed. This way, you know that you will not pay more than the market price for gas (baseFeePerGas) and will be refunded any extra funds. minus your tip.
- failOnLowFee (true / false): The estimated baseFee + priorityFee compared with the current medium baseFee + priorityFee calculated from recent block history. In the time between a transaction being created and signed, blockchain fees can fluctuate. If the current blockchain fee exceeds the initial estimated fee, the transaction will automatically fail to avoid getting stuck with no confirmations.
Non EIP-1559 transactions
- gasPrice* (gwei): Price per gas unit. If both networkFee and gasLimit are specified, the gasPrice is defined automatically.
- failOnLowFee (true / false): The medium calculated gasPrice and the set gasPrice of the transaction are compared. The allowed delta is calculated as a function of the gasPrice. If the difference is larger than the delta, the transaction will automatically fail.
* Only two out of three of these parameters may be set at any time.
The gasPrice and priorityFee parameters are automatically calculated based on the transaction speed selected in the feeLevel parameter.