L1 Calldata Costs

Cost

⎊ L1 Calldata Costs represent the direct transaction fee, denominated in the Layer 1 native currency, incurred to permanently store data on the base blockchain, typically Ethereum. This expense is the primary variable cost component for Layer 2 scaling solutions, as transaction batches must be posted to the L1 for data availability and eventual state verification. Minimizing this overhead is a central objective in rollup design to ensure competitive fee structures.