Wormhole Chains — Arbitrum

1. What is Arbitrum?

Arbitrum is an L2 scaling solution for Ethereum. On Arbitrum, users can do all things they are able to do on Ethereum — use dApps, deploy smart contracts, conduct ERC20 transactions, etc. — but the corresponding transactions are cheaper and faster. Arbitrum’s flagship product, Arbitrum Rollup, is an Optimistic rollup protocol that inherits Ethereum’s security while minimizing the amount of data used on-chain. Arbitrum uses, just like Ethereum, the Solidity programming language, and numerous integration options provide standard Ethereum front-end tooling for Arbitrum, making it easy to work with.

2. Why do we need Arbitrum? Is something wrong with Ethereum?

Generally speaking, no — nothing is wrong with Ethereum. But: the Ethereum blockchain only allows about 10–20 transactions per second (TPS) to be computed. When this limit is reached, users are forced to compete against each other for their transactions to be completed ahead of others, which causes transaction fees to increase — reaching hundreds of dollars at times of very high usage, like popular NFT mints.

3. How does Arbitrum work?

To understand how Arbitrum works, we first need to understand how rollups work:

A. ZK-Rollups

ZK-rollups rely on cryptographic proofs, called ZK-STARKs, to validate data and perform computations off-chain, eliminating the need for trust in validators while still having the ability to perform increased numbers of transactions.

B. Optimistic Rollups

Optimistic rollups assume all L2 transactions sent to the main chain are valid unless a node suspects that a fraudulent transaction is occurring. By performing validity proofs only when fraud is suspected, optimistic rollups increase transaction speed and throughput. More details can be found here.

So, what are “Arbitrum Rollups”?

Arbitrum Rollups are an advanced Optimistic rollup protocol that store very little data on-chain for optimal scalability.

4. Who’s behind Arbitrum?

Arbitrum is being developed by Offchain Labs, the brainchild of Ed Felten, professor at Princeton and former Deputy U.S. Chief Technology Officer in the Obama White House, and his Co-Founders CEO, Steven Goldfeder, and CTO, Harry Kalodner. Offchain Labs was founded in 2018, but the tech was first developed at Princeton. You can find a YouTube video where the tech was discussed back in early 2015. Learn more about Offchain Labs in this TechCrunch article.

5. Anything else?

Speed & Costs

While Ethereum only averages 10–20 transactions per second, Arbitrum can handle 7x that transaction load. Transactions on Ethereum cost several dollars (at times of high usage, they can reach up to several hundred dollars), while they only cost a few cents on Arbitrum.

Native Token

Arbitrum does not have a native token.


Trust Wallet
Math Wallet
…and many others

Block Explorer


Programming Languages


Documentation & GitHub


Contact & Socials

Stay up to date with Arbitrum by following their social channels:

6. Wormhole Noob? No problem!

If you’re new to Wormhole, here’s what you need to know:

7. Wormhole’s supported networks

Wormhole allows users to send assets to and from any of the supported chains without double-wrapping the asset. It enables seamless access to each network’s vibrant DeFi & NFT ecosystems!

8. Join the ever-growing Wormhole community

If you have questions, need support, or just want to connect, join the Wormhole community and keep up to date with our upcoming announcements. We’re always happy to hear feedback — join our Discord, and drop us a comment!



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Cross-chain interoperability protocol connecting high value blockchains