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Blockchain Glossary

Glossary

Blob Base Fee

Ethereum's separate fee market for blob data (EIP-4844) — adjusts independently of normal gas based on how full recent blocks' blob counts have been.

EIP-4844 introduced blobs as a separate fee market. The blob base fee adjusts each block based on excess_blob_gas: if recent blocks have used more than the target number of blobs, blob fees rise sharply; if under target, they fall.

Because the blob market is independent of execution gas, a busy period for rollups doesn't necessarily mean expensive normal transactions, and vice versa. The blob base fee is the single most-watched signal of rollup data demand on Ethereum.