How Does the “Base Fee” and “Priority Fee” System Work under EIP-1559?

The base fee is the minimum price per unit of gas required for a transaction to be included in a block, and it is determined algorithmically by network demand. The priority fee is an optional "tip" paid by the user to the validator to incentivize them to prioritize the transaction.

Users set a "max fee" which covers both. If the max fee is higher than the base fee plus the priority fee, the excess is refunded.

What Is EIP-1559 and How Did It Change the Gas Fee Mechanism?
How Does EIP-1559 Change the Fee Market on Ethereum?
How Does the ‘EIP-1559’ Upgrade Affect Ethereum’s Transaction Fee Structure?
What Is the Role of EIP-1559 in Modifying the Ethereum Fee Market?
What Is EIP-1559 and How Did It Change the Gas Fee Mechanism on Ethereum?
How Does EIP-1559 Affect the Predictability of Gas Fees for Smart Contract Execution?
How Does EIP-1559 Affect Gas Fee Predictability?
How Does the Implementation of EIP-1559 Change the Dynamic of Transaction Fees for Miners?

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