Optimism
The original OP Stack chain and coordinator of the Superchain, a federation of shared-standard L2s.
OP Mainnet is an optimistic rollup built on the OP Stack, the same framework used by Base, Ink, Unichain, Soneium, World Chain, and other Superchain members. It uses Cannon fault proofs (Stage 1) with permissionless challenges, and its Retroactive Public Goods Funding program has redistributed hundreds of millions of dollars in OP tokens to ecosystem projects. It anchors the largest L2 ecosystem by number of chains, with revenue-share to the OP Collective from every Superchain member.
- TVL around $5.6B in April–May 2026 per L2BEAT and DeFiLlama, the third-largest optimistic rollup.
- Stage 1 rollup with live Cannon fault proofs; ~2s block times, sub-cent fees, 7-day canonical withdrawal window.
- Anchors the Superchain, which spans Base, World Chain, Ink, Unichain, Soneium, Mode, Zora, Celo, and others (~12+ production chains, combined ~$6B+ TVL per L2BEAT).
- ERC-7802-based cross-Superchain interop is rolling out in 2026, enabling atomic transfers between member L2s.
- Live lending markets include Aave V3, Compound V3, Sonne, and Silo, plus Velodrome as the main gauge-directed DEX.
Frequently asked questions
What is the Superchain and how does it affect OP Mainnet's value?
The Superchain is a federation of L2s that all use the OP Stack, share a security model, and route revenue back to the Optimism Collective. That means OP Mainnet's economic exposure is bigger than its own TVL suggests: it captures a slice of activity from every Superchain member, including Base.
Are OP Mainnet and Base the same chain?
No. They are separate L2s that share the OP Stack codebase but run their own sequencers, state, and TVL. They are both members of the Superchain, which means they will eventually support atomic cross-chain messaging once interop ships, but today assets have to be bridged between them.
What is Optimism's fee model?
OP Mainnet charges an L2 execution fee plus an L1 data fee for blob posting to Ethereum. Post-Dencun, both are low: median transaction cost is under one cent. Sequencer revenue is split between chain operations and the OP Collective, which funds retroactive grants.