Launch a chain Run a node Use the bridge How it works Notices Notices Temporary pause on new Stylus activations Glamsterdam compatibility notice for Arbitrum Sepolia chains Upgrade notice for ArbOS 61 Upgrade notice for ArbOS 51 Upgrade for the Fusaka transition

Notices

Upgrade notices and required actions for Arbitrum chains and node operators.

Request an update

Upgrade notices for Arbitrum chains and node operators, including ArbOS upgrades and network transitions.

Fusaka compatibility

What the transition to Fusaka requires.

ArbOS 61

Activation on Arbitrum One, Nova, and Sepolia.

ArbOS 51

Activation on Arbitrum One, Nova, and Sepolia.

How is this guide?

Temporary pause on new Stylus activations

The Arbitrum Security Council has temporarily paused new Stylus contract activations on Arbitrum One and Arbitrum Nova as a security measure

For AI agents: a documentation index is available at the root level at /llms.txt and /llms-full.txt. Append .md to any docs page URL for the markdown version of that page.

Arbitrum docs

Ecosystem

Arbitrum.io Arbitrum chains Arbitrum Foundation Arbitrum whitepaper

Products

Portal Bridge Network status Governance docs

Community

Discord Twitter Youtube Medium Blog

Resources

Support Bug Bounties Research forum Careers