Offchain Labs
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Offchain Labs

Arbitrum Rollup Testnet: full-featured and open to all

Arbitrum Rollup is the first and only fully featured EVM-compatible Optimistic Rollup with a testnet that’s open to all.

We at Offchain Labs are excited to announce a brand new Arbitrum Rollup testnet on Ethereum’s Kovan test network. This is an open testnet allowing anyone — yes, that includes you — to deploy Solidity contracts on Arbitrum Rollup now. Today’s release is a major upgrade from our previous testnet release and runs on the newly upgraded Arbitrum software stack.

Try Arbitrum Rollup today

Our February testnet launch was the first — and to date only — fully-functional EVM Optimistic Rollup on Ethereum testnet. Today we’re excited to take that a big step further by hosting an open Arbitrum Rollup chain empowering everyday users to deploy contracts at scale in just minutes and without needing to download any of our software.

Our testnet also offers a full block explorer and a token bridge so anyone can deposit and withdraw ETH and ERC-20/721 tokens.

Over the next several weeks, we’ll be announcing more details about our mainnet launch timeline, feature set, and launch partners, but today’s announcement is all about you. No matter who you are or what you’re working on, you can deploy contracts on Arbitrum Rollup’s testnet right now. And it’s easy to get started.

Building on Arbitrum is easy

Building on Arbitrum is as simple as changing your RPC endpoint to It’s that easy.

Our new software stack was built with a core principle in mind: make the Arbitrum developer experience feel exactly like Ethereum. Arbitrum runs EVM code directly and doesn’t require any custom tooling or transpilers. You can use your preferred Ethereum developer setup to build and deploy on Arbitrum.

Get started building on Arbitrum in five minutes or less

Once you’ve deployed your contract, head over to the Arbitrum block explorer to find your transaction and see its gas usage stats.

What’s included?

This is a fully featured Arbitrum Rollup chain, which includes:

You can also launch your own Arbitrum chain if you want, by following the instructions on our developer site. But why not try our open hosted chain first?

How can you help?

This is a testnet, and the best way you can help is by helping us test it. Try it out and give us feedback! We’re working hard to ready our code for mainnet, and your feedback is a key part of this.

Did things work well? Did something not work quite right? Is there some additional feature that you’d like? We want to know!

Are you ready to roll out with us when we launch Arbitrum on mainnet? Fill out this form and we’ll be in touch.

And definitely come join the conversation on our Discord.

Show me the benchmarks?!

Glad you asked! In the theme of today’s launch, we created a tool to empower you to benchmark your own transactions. Our block explorer generates and displays instant gas usage statistics for every transaction.

So go ahead, deploy some contracts and check out the gas savings.

What’s next?

We’re readying Arbitrum for a mainnet Ethereum launch. Over the next several weeks, we will release a series of small upgrades to Arbitrum, and redeploy our testnet to incorporate these changes as we release them.

The remaining pre-mainnet work will be mostly around bug-fixes and Arbitrum Virtual Machine performance. But we have some other really exciting features coming in the next few weeks. <Aherm. Cough, cough> BLS signatures and more <cough>.

To get started with our testnet, check out:

If you have any questions, join our Discord:

Want to launch on mainnet with us? Fill out this form and we’ll be in touch.

You can email us at:




Creating Arbitrum, an Ethereum scaling solution

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Offchain Labs

Offchain Labs

We’re Building Arbitrum, a scaling solution for Ethereum. Learn more at and

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