Home Academy Compare Arbitrum vs Optimism: Ethereum Layer 2 Rollup Comparison
Layer 2

Arbitrum vs Optimism: Which is Better?

Compare Arbitrum and Optimism Layer 2 rollups. Explore differences in technology, TVL, governance, and ecosystem between these leading Ethereum scaling solutions.

Updated 2026-03-08 Layer 2 Comparison
AR
Arbitrum (ARB)
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OP
Optimism (OP)
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Arbitrum vs Optimism at a Glance

Feature
ARB
OP
Rollup Type
Optimistic rollup with interactive fraud proofs
Optimistic rollup with single-round fault proofs
Fraud Proof System
Multi-round interactive proving (Arbitrum BOLD)
Single-round fault proofs (Cannon)
EVM Compatibility
Custom AVM; Nitro compiles to WASM for execution
EVM-equivalent; runs unmodified Ethereum execution client
TVL
Largest L2 by total value locked
Second-largest L2 by total value locked
Governance Token
ARB token for Arbitrum DAO governance
OP token for Optimism Collective governance
Ecosystem Strategy
Arbitrum One (general) and Arbitrum Nova (gaming/social)
OP Stack powers Base, Zora, Mode, and the Superchain vision
Transaction Fees
Generally lower fees due to Nitro compression
Competitive fees, reduced further after EIP-4844
Developer Tooling
Stylus allows Rust, C, and C++ smart contracts
Standard Solidity/Vyper tooling; EVM equivalence simplifies migration
Sequencer
Centralized sequencer operated by Offchain Labs
Centralized sequencer operated by OP Labs
Governance Model
Token-weighted DAO with Security Council
Bicameral system: Token House and Citizens' House
Layer 2

What is Arbitrum?

Arbitrum is an Ethereum Layer 2 scaling solution developed by Offchain Labs that uses optimistic rollup technology to process transactions off-chain while inheriting Ethereum's security.

Ticker: ARB Since 2021
Layer 2

What is Optimism?

Optimism is an Ethereum Layer 2 scaling solution that uses optimistic rollup technology. It is developed by OP Labs and serves as the foundation for the OP Stack, a modular framework for building L2 chains.

Ticker: OP Since 2021

Key Differences

Arbitrum uses multi-round interactive fraud proofs (BOLD), while Optimism uses single-round fault proofs (Cannon), leading to different security trade-offs.

Optimism's OP Stack has become a shared framework adopted by Base, Zora, and others forming the Superchain, while Arbitrum focuses on its own Orbit chain framework.

Arbitrum's Stylus enables smart contracts in Rust, C, and C++, while Optimism maintains strict EVM equivalence for maximum Ethereum compatibility.

Arbitrum consistently leads in TVL among L2s, though Optimism's combined Superchain ecosystem narrows the gap.

Optimism features a unique bicameral governance model with a Token House and Citizens' House for retroactive public goods funding.

Which Should You Choose?

Arbitrum leads in TVL and offers more developer flexibility through Stylus multi-language support. Optimism's strength lies in the OP Stack and Superchain ecosystem, which has attracted major partners like Coinbase (Base). Both are strong Ethereum L2s serving different strategic visions.

Frequently Asked Questions

Is Arbitrum faster than Optimism?
Both offer near-instant transaction confirmation on L2. Final settlement on Ethereum takes about 7 days for both due to the optimistic rollup challenge period.
Which L2 has lower fees?
Fees are similar and depend on Ethereum L1 gas prices. Both benefited significantly from EIP-4844 (proto-danksharding), which reduced data posting costs.
What is the OP Stack?
The OP Stack is an open-source modular framework for building Layer 2 chains. It powers Optimism mainnet, Base (by Coinbase), Zora, Mode, and other chains forming the Superchain.
Can I use the same wallet on both?
Yes. Both Arbitrum and Optimism are EVM-compatible, so any Ethereum wallet like MetaMask works on both networks by simply adding the chain.
What is Arbitrum Stylus?
Stylus is an Arbitrum feature that allows developers to write smart contracts in Rust, C, and C++ alongside Solidity, enabling better performance and access to a broader developer base.
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