Chain-Specific

Arbitrum One

The primary Arbitrum L2 network using Optimistic Rollup technology; the largest L2 by TVL as of 2026.

Arbitrum One — Arbitrum One is the largest Ethereum Layer 2 network by total value locked (TVL), built by Offchain Labs using optimistic rollup technology. It offers transaction costs 10-50x lower than Ethereum mainnet, hosts a mature DeFi ecosystem including GMX, Aave, and Uniswap, and settles all transactions on Ethereum for security.

What Is Arbitrum One?

Arbitrum One is an optimistic rollup that processes transactions off Ethereum mainnet while posting transaction data to L1 for security verification. Launched in August 2021, it quickly became the leading L2 by TVL, hosting over $10 billion in deposited assets at peak. The chain uses Nitro technology — a WASM-based execution environment that compresses transactions efficiently.

Arbitrum One DeFi Ecosystem

Arbitrum One hosts the most mature L2 DeFi ecosystem. GMX (perpetual trading), Aave and Radiant (lending), Uniswap and Camelot (spot DEX), and Pendle (yield trading) are among the flagship protocols. The ARB governance token, airdropped in March 2023, governs the Arbitrum DAO treasury and protocol upgrades.

Arbitrum for Trading

Arbitrum's combination of low fees, deep liquidity, and Ethereum security makes it a preferred chain for DeFi trading. OpenLiquid supports Arbitrum One for volume generation, enabling projects to build trading activity in one of the most liquid L2 environments. Gas costs on Arbitrum are typically $0.05-0.50 per transaction.

Related Terms

Chain-Specific

Arbitrum Nova

A lower-cost Arbitrum chain using AnyTrust technology for high-volume, low-value applications like gaming and social.

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Ethereum Mainnet

The primary Ethereum blockchain where all real-value transactions occur, as distinct from testnets like Sepolia or Goerli.

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Base (L2)

Coinbase's Ethereum L2 built on the OP Stack, launched 2023; known for low fees and Coinbase ecosystem integration.

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Sequencer (L2)

The entity responsible for ordering and batching transactions on an L2 rollup before posting them to the base layer.

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Frequently Asked Questions

Common questions about Arbitrum One in cryptocurrency and DeFi.

Arbitrum One is an optimistic rollup posting full transaction data to Ethereum (maximum security). Arbitrum Nova uses AnyTrust technology, posting data to a committee instead of L1, achieving even lower costs at the expense of some security assumptions. Nova targets gaming and social applications.

The official Arbitrum Bridge transfers ETH and tokens from Ethereum mainnet. The process takes about 10 minutes for deposits. Withdrawals to Ethereum require a 7-day challenge period. Third-party bridges like Across and Stargate offer faster transfers.

ARB is Arbitrum's governance token, airdropped to early users in March 2023. It grants voting power over the Arbitrum DAO, which controls a multi-billion-dollar treasury and governs protocol upgrades. ARB does not pay gas — Arbitrum uses ETH for transaction fees.

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