What it is
The base fee is a core element of Ethereum's EIP-1559 transaction fee mechanism. It is a network-determined price for including a transaction in a block, which automatically adjusts up or down by 12.5% per block based on how full the previous block was. This dynamic adjustment aims to keep block utilization around 50%, making fees more predictable. Unlike the priority fee, the base fee is not paid to validators.
The base fee's behavior is a key indicator of Ethereum network activity and congestion. When the network is busy, the base fee rises, making transactions more expensive. Conversely, it falls during periods of lower demand. News and analytics platforms frequently report on the average base fee or the total ETH burned from base fees, providing insights into network health and the deflationary pressure on ETH's supply. Users need to understand base fees to estimate transaction costs.
Why it matters
The base fee determines a significant portion of your Ethereum transaction cost and reflects network demand.
Reviewed under editorial standardsUpdated September 26, 2026Not investment advice