Glossary
Base Fee
Under EIP-1559, the per-gas fee algorithmically set by the protocol and burned with each transaction — separate from the optional tip paid to the proposer.
The base fee adjusts block-by-block: up about 12.5% when the previous block was over 50% full, down about 12.5% when under. The adjustment converges on whatever level keeps blocks half full on average.
It is burned, not paid to any party — which permanently removes ETH from circulation and is what tipped Ethereum into net-deflationary issuance in busy periods between 2022 and 2024. Users still tip the proposer on top of the base fee for fast inclusion.