Please note that this site is the TESTNET; for MAINNET, visit and SPACE ID 2.0

To register a new .arb name, what are the format requirements?
Name length: at least 3 characters.
•  Case sensitive: only lowercase letters allowed, no capital letters.
•  Certain characters including “:”, “/” are not supported.
•  Emojis are generally supported.
•  Different languages are generally supported.
Which chain is .arb’s NFT contract deployed on?
•  Arbitrum One. Such that you need to have some ETH on Arbitrum One to mint your .arb NFT. You can use the official bridge ( to transfer ETH from Ethereum to Arbitrum One if needed.
Can .arb names work on both Arbitrum One and Arbitrum Nova?
•  Yes, while the .arb NFT contract is deployed on Arbitrum One, your Arbitrum Nova address is also recorded in the contract and could be edited if needed. Such that in wallets that have integrated .arb SDK, your .arb names will work on both Arbitrum One and Arbitrum Nova.
Are all .arb domain names available to register? Why are some reserved?
•  A short list of names will be reserved, mostly those associated with notable Web3 projects (especially Arbitrum eco-system dApps), as we believe those could be utilized to accelerate .arb adoption and add more value to the whole community.
•  Other than those, all .arb domain names are available to register (subject to format compliance).
What is a primary name? And why shall I set a primary name?
•  A primary name makes your Arbitrum address point to your .arb name (a process formally called Reverse Resolution), such that you will be able to see your .arb name displayed in partner dApps, replacing the complex addresses to achieve an improved interface.
•  Setting your primary name only requires a small amount of gas fee and we encourage everybody to do it, as it is a vital step to make your .arb name a central piece to your web3 identity.
Instead of registering a new .arb, if I have bought an existing .arb from NFT marketplace, what shall I do before putting to use?
•  You should edit the Arbitrum address record first, using your address to replace the existing address from the previous owner, to ensure that your newly bought .arb name resolves correctly to your current address.
What happens when my registration approaches deadline?
•  You can extend your .arb name anytime during the registration period and within 90 days after it expires, which is a 90-day grace period. During the grace period, the .arb name will be reserved only for you to expand its registration. After the grace period, the name will not be reserved and will be open to the public to register.
What is NFT metadata? And why do I need to refresh it on NFT marketplace sometimes?
•  NFT metadata is a set of data that describe the characteristics and display the content relating to the NFT, including for example the .arb skin design image. If you find your .arb NFT image is not properly displayed on NFT marketplace, or your NFT is not properly categorized, you can simply click the “Refresh Metadata” button and refresh the page.