Arbitrum

Arbitrum is an optimistic rollup that settles to Ethereum, offering EVM-compatible execution with generally lower fees than L1.

Chain IDs

Network	Chain ID
Arbitrum One (mainnet)	42161
Sepolia (testnet)	421614

Technical summary

• Scaling model: Optimistic rollup secured by Ethereum.
• VM: EVM compatible; existing Ethereum tooling and ABIs apply.
• Fees: Lower gas costs than Ethereum L1 for typical workloads.
• Wallets: Safe smart-account deployment and usage via IBEx when X-Blockchain-Id matches the table above.

API configuration

X-Blockchain-Id: 42161

Testnet:

X-Blockchain-Id: 421614

See also

• Supported blockchains
• Safe Smart Account