

Celestia is a modular blockchain designed exclusively for data availability (DA). It decouples consensus and data availability from execution, meaning rollups and appchains can use Celestia purely to post and verify transaction data without running a full execution environment. This is the modular blockchain thesis: specialize each layer (execution, settlement, consensus, DA) rather than combining all functions into a monolithic chain.
Light nodes in Celestia use Data Availability Sampling (DAS): they randomly sample small chunks of block data and use erasure coding to probabilistically verify that the full block is available without downloading the entire block. This allows light nodes to verify DA with minimal hardware, enabling a decentralized DA layer that scales with the number of light nodes rather than validator count.
TIA is used to pay for blob space (the unit of DA on Celestia), participate in governance, and stake for consensus security. Rollups posting data to Celestia denominate fees in TIA. There is also a bootstrapping mechanism where new chains launching on Celestia can receive TIA through “interchain airdrops” funded by the team.
EIP-4844 introduced blob transactions to Ethereum at significantly lower cost than calldata, partially eroding Celestia’s cost advantage. The key differentiator: Celestia’s DA layer is purpose-built with higher throughput, and it serves non-Ethereum ecosystems (Cosmos, Sovereign rollups). Ethereum blobs are pruned after ~18 days; Celestia also prunes but offers a specialized DA marketplace. The competitive dynamic is real and worth tracking.
Celestia sits at the base of a stack where rollups (Eclipse, Manta, others) use it for DA while settling on Ethereum or operating as sovereign chains. The bet is that DA becomes commoditized infrastructure with significant fee volume as rollup throughput scales.