Base Fee
Protocol set minimum gas price per unit under EIP 1559.
The base fee is the protocol-calculated minimum price per unit of gas required for a transaction to be included in a block under Ethereum's EIP-1559 fee mechanism. It adjusts automatically with network demand rather than being selected by a validator. On Ethereum, the paid base fee is burned instead of going to the block proposer.
Gas measures the computational and storage work performed by a transaction. Total execution cost is the gas actually used multiplied by the effective gas price. The base fee represents one component of that price. A sender also offers a priority fee, or tip, and sets a maximum fee per gas that limits what the wallet is willing to pay.
The protocol compares parent-block gas usage with a target. Usage above the target raises the next base fee, while usage below it lowers the fee. Ethereum blocks can temporarily use more gas than the target, providing elastic capacity during demand spikes, but sustained congestion makes base fees rise. The adjustment is bounded from one block to the next, which improves predictability without guaranteeing a cheap transaction.
For example, if the base fee is 20 gwei, the user offers a 2 gwei priority fee, and the maximum fee is high enough, the effective price may be 22 gwei per gas. Any unused difference under the maximum is not charged. Wallet estimates often reserve room for base-fee growth while a transaction waits, helping avoid underpriced transactions.
The base fee matters because it gives users a clearer market price for block space and reduces the need for blind first-price gas auctions. Burning also links network usage to ETH supply. That does not mean every busy period makes ETH permanently deflationary because new issuance and burned fees must be compared over the same interval.
Common mistakes include confusing gas limit with gas price, assuming a failed transaction costs nothing, or setting a maximum fee below the future base fee. Reverted execution still uses gas. A priority fee improves inclusion incentives but cannot bypass contract rules or guarantee immediate confirmation. Before signing, review estimated total cost, transaction purpose, and current network conditions. EIP-1559-inspired chains may change fee formulas or destinations, so consult the relevant network documentation.
Frequently asked questions
- No person or validator chooses Ethereum's base fee. The protocol calculates it for each block from the parent block's base fee and gas usage relative to a target. When blocks use more than the target, the fee rises; when they use less, it falls. Wallets estimate future values, so the final charged amount may differ.
- The priority fee, often called a tip, is the amount per gas paid to encourage a validator to include a transaction. The sender sets a maximum priority fee and maximum total fee. During normal conditions a modest tip may work, while urgent competition can raise it. A high tip cannot make an invalid transaction succeed.
- On Ethereum, the base fee paid for used gas is burned, permanently removing that ETH from circulating supply. The block proposer generally receives the priority fee and may receive other execution value. Other EIP-1559-style networks can implement different destinations or parameters, so users should verify the specific chain rather than assume every base fee is burned identically.