What is Avail DA?
Avail DA is a modular data availability layer purpose-built for rollups — providing scalable, verifiable DA without execution overhead.
Rollups need somewhere to post their transaction data so that anyone can verify it's available. Traditionally this means posting to Ethereum L1, but that's expensive and doesn't scale — every byte of calldata competes for the same limited block space.
Avail DA is a purpose-built data availability layer that solves this. Instead of piggybacking on a general-purpose L1, rollups post their data to Avail, where it's ordered, committed to with cryptographic proofs, and made available for verification — all without Avail needing to execute any of it.
A modular blockchain separates its core functions into specialized layers:
Avail sits at the DA layer. It doesn't execute transactions, validate state transitions, or handle settlement. It does one thing — ensures the data your rollup posts is available — and it does it well.
Avail validators don't re-execute your transactions. They attest that data has been correctly published and committed to. This means Avail can support much larger blocks than chains where validators must process every transaction.
Avail uses KZG polynomial commitments to generate validity proofs for block data. These proofs are included in every block header, allowing anyone to verify data correctness without downloading the entire block.
Light clients on Avail randomly sample small portions of each block to probabilistically verify that the full data is available. Combined with erasure coding, this gives near-100% confidence with minimal bandwidth. This means even devices with limited resources can verify DA without trusting a full node.
Each application on Avail gets its own App ID. Your rollup only needs to download the data posted under its App ID — not the entire block. Other chains using Avail at the same time don't affect your throughput or costs.
Avail DA is designed for rollup developers and infrastructure teams who need:
How Avail fits in the modular stack
| Layer | Responsibility | Example |
|---|---|---|
| Execution | Process transactions and update state | Your rollup (OP Stack, Arbitrum Orbit, ZK chains, etc.) |
| Settlement | Verify execution proofs and resolve disputes | Ethereum |
| Data Availability | Guarantee that transaction data was published and is retrievable | Avail DA |
What makes Avail DA different
No execution overhead
Validity proofs, not just attestations
Data availability sampling (DAS)
App IDs for data isolation
Who uses Avail DA
- A scalable DA layer that won't bottleneck their rollup's throughput
- Cryptographic guarantees (not just committee attestations) that data is available
- A chain-agnostic solution that works with any execution environment — EVM, SVM, custom VMs
Note
Next steps
- Learn how Avail DA works under the hood — DAS, erasure coding, and consensus.
- Ready to build? Jump to the Build section to integrate your rollup with Avail DA.
- See Networks & Endpoints for RPC URLs and contract addresses.
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