MetaMask is a crypto wallet that connects by default to the Ethereum mainnet. You can find the extension and mobile app on the official MetaMask website.
To connect to networks like Arbitrum, you'll need to add some blockchain information to MetaMask. This includes a chain ID, custom RPC URL, and network name. To add an Arbitrum token, you’ll also need to import the correct token address.
Adding new blockchains to MetaMask is a transferable skill, and you can apply the skill to add other EVM networks like BNB Smart Chain (formerly Binance Smart Chain) and Polygon.
To use the Arbitrum blockchain, you’ll need a compatible crypto wallet like MetaMask. However, MetaMask doesn’t automatically have Arbitrum added as a default blockchain. Setting up your wallet to connect to Arbitrum is a simple process and can be done quickly.
Installing and setting up MetaMask
1. MetaMask is available for Chrome, iOS, or Android on the MetaMask website. Make sure to check you’re using the official website and downloading the legitimate extension.
2. After installing the extension, you’ll see the MetaMask welcome page. Click [Get Started] to begin.
3. If you want a new wallet, click the [Create a Wallet] button. You can also import an existing wallet with its seed phrase using the [Import wallet] option.
4. If you’d like to share anonymous usage data with Metamask, you can do so at this stage. Accepting or refusing this will not affect your wallet usage.
5. Create a secure password for your wallet. Note this isn’t your seed phrase. The password simply prevents people from accessing your wallet through your device. If you forget your password, you can always retrieve your crypto with your seed phrase.
6. After choosing your password, MetaMask will provide some useful information regarding your wallet’s seed phrase. Read through it carefully if you’re not familiar with how crypto wallets work.
7. You’ll now see with your seed phrase. Click the lock to view the phrase and take note of the words in the correct order. Store the phrase securely (preferably offline) and never share it with anyone. This string of words is the final backup of your wallet’s contents. Click [Next] to continue.
8. You’ll need to repeat your seed phrase by selecting the words in the correct order. Click [Confirm] once finished.
9. Your MetaMask wallet will now be ready to use. Click [All Done] to view your new wallet.
10. You can pin Metamask to your Chrome browser by clicking the puzzle icon and selecting it. MetaMask will initially only be connected to Ethereum. Next, we’ll look at how to connect Metamask to Arbitrum.
Configuring the wallet
1. Adding Arbitrum functionality to your wallet involves adding some simple network details to Metamask. First, open Metamask and click the network dropdown menu.
2. Now, click [Add Network] on the pop-up.
3. You’ll need to add the following details on the [Add a network] page that will open. Click [Save] when you’re finished.
4. You’ll now successfully be connected to the Arbitrum network.
Adding Arbitrum tokens to MetaMask
For Arbitrum tokens to appear on the wallet UI, you need to manually add them. Note your wallet will still receive tokens that haven’t been imported, but they just won’t show up natively.
1. First, head to Arbiscan and find the token contract and details of the token you want to add. If the token isn’t on Arbiscan, get the contract address from the project’s official website. You should always be careful of fake contracts created by scammers.
2. Return to MetaMask and click [Import tokens].
3. Paste in the token’s contract address and MetaMask should fill in the rest of the details. If not, manually add them. To finish, click [Add Custom Token].
4. Click [Import Tokens].
5. Your wallet will now display the balance of the token you just added.
After setting up the Arbitrum mainnet in MetaMask, you’re free to start sending crypto, collecting NFTs, and using DeFi DApp smart contracts. You can even swap tokens within the extension. Make sure, however, to have ETH in your wallet to pay your transaction costs. You can get this by using an Arbitrum bridge for your ETH on the Ethereum mainnet.
MetaMask isn't just for Ethereum and Arbitrum as well. The wallet actually supports the whole Ethereum Virtual Machine (EVM) ecosystem, including BNB Smart Chain. With the skills in this tutorial, you’ll now be able to add more chains and begin using them with the correct details.