Arbitrum scales your Ethereum contracts today.

Off-chain smart contracts with on-chain security.

We make smart contracts easier and cheaper to develop and run at massive scale, with production level security. Our developer tools do the heavy lifting to add a flexible second layer to your decentralized application architecture, so that you can focus on business logic and user experience. Beginning with the Ethereum blockchain, we're coming soon to a blockchain near you.

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Recent Press

Arbitrum's three powerful scaling modes


Ideal for contracts that don't have a fixed set of participants or validators, Arbitrum Rollup contracts enjoy the fully trustless security of the Ethereum blockchain, all while simultaneously increasing the contract's capacity and greatly reducing gas costs. 


Perfect for contracts that have a fixed set of participants, Arbitrum channels move all contract computation and storage offchain. You can think of these as powerful state channels with a highly efficient dispute resolution mechanism that guarantee privacy and remains off-chain even in the presence of disputes.


Interested in deploying your own sidechain with a named set of validators? Arbitrum sidechains are the only sidechain technology with the AnyTrust guarantee that ensures correct execution even if only a single validator behaves honestly.

Why Use Arbitrum?


Whether you're using Rollup, channels, or sidechains, Arbitrum reduces costs while increasing contract capacity and speed without compromising on security or interoperability.


No new coding paradigms or programming langauges to learn here. The Arbitrum toolchain automatically converts Ethereum contracts to Arbitrum contracts.


Nobody other than the participants of an Arbitrum channel can see its code or its internal state. Only the public actions of a contract, such as payments it makes, are visible to the world.

Dive Deeper

Want to learn all about how Arbitrum can enable you to build new applications? Read about how Arbitrum works.

Learn how it works

Want to learn even more details about how Arbitrum works? Read our old academic paper, published at USENIX Security 2018.

Read the old Academic paper

Ready to dig into the code and start using Arbitrum today with our developer preview? Check out our developer website

Read the code


Ed Felten

Ed Felten is Co-founder and Chief Scientist at Offchain Labs. He is on leave from Princeton University, where he is the Robert E. Kahn Professor of Computer Science and Public Affairs. From 2015 to 2017 he served at the White House as Deputy United States Chief Technology Officer and senior advisor to the President. He is an ACM Fellow and member of the National Academy of Engineering. Outside of work, he is an avid runner, cook, and L.A. Dodgers fan.

Steven Goldfeder

Steven Goldfeder is Co-founder and Chief Executive Officer at Offchain Labs. He holds a PhD from Princeton University, where he worked at the intersection of cryptography and cryptocurrencies. He is a co-author of Bitcoin and Cryptocurrency Technologies, the leading textbook on cryptocurrencies.

Harry Kalodner

Harry Kalodner is Co-founder and Chief Technology Officer at Offchain Labs where he leads the engineering team. Before the company he attended Princeton as a Ph.D candidate where his research explored economics, anonymity, and incentive compatibility of cryptocurrencies. When not up at 3:00am writing code, Harry occasionally sleeps.


Upcoming Events

Members of our team will be at these upcoming events. Feel free to email us at [email protected] if you'd like to connect at any of these venues.

Event Schedule


We’re looking for motivated and experienced developers to join our team. For more information, email us at [email protected].

Current Openings
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