Ethereum blob fee (EIP-4844) now
The price of blob space on Ethereum — the data layer-2 rollups pay for — and what one blob costs right now.
The blob base fee: no data yet. We show nothing rather than a guess.
Specification: EIP-4844 (GAS_PER_BLOB = 2^17), blob target and maximum raised in EIP-7691.
Questions and answers
What is a blob?
A large piece of data (128 KiB) that a transaction can attach since EIP-4844. Nodes keep blobs for a limited time only, which is why blob space is priced separately and is cheap compared with storing the same data in normal transaction data.
What is the blob base fee?
The price per unit of blob gas. Every blob is 131,072 blob gas (2^17). Like the normal base fee, it rises when blocks carry more blobs than the target and falls when they carry fewer, and it is burned.
Why do layer-2 fees depend on the blob fee?
Rollups such as Arbitrum, Optimism and Base post their transaction data to Ethereum in blobs. The L1 data fee each user pays is that rollup's blob cost shared across the transactions in the batch.
Has the number of blobs per block changed?
Yes. Later upgrades raised the target and the maximum number of blobs per block (EIP-7691 in the Pectra upgrade among them). The cost of one blob is still blob base fee × 131,072.