How to add Optimism network in MetaMask?

Adding Optimism to MetaMask requires a custom RPC URL; incorrect URLs risk fund loss. Ensure sufficient ETH for gas fees on both Ethereum (L1) and Optimism (L2), understanding the bridging process between layers is crucial.

Mar 14, 2025 at 12:55 pm

Key Points:

• MetaMask's native support for Optimism is limited. Adding Optimism requires interacting with a custom RPC URL.
• Incorrect RPC URLs can lead to transaction failures and potential loss of funds. Double-check your source carefully.
• You'll need sufficient ETH in your MetaMask wallet to cover gas fees on both the Ethereum mainnet and the Optimism network.
• Understanding the differences between L1 (Ethereum) and L2 (Optimism) is crucial for navigating the network.

How to Add the Optimism Network to MetaMask

MetaMask doesn't directly list Optimism in its default network selection. To add it, you need to manually configure a custom network. This involves providing MetaMask with specific network details, such as the RPC URL, chain ID, and currency symbol. Incorrectly entering this information can prevent your wallet from connecting to the Optimism network. Always obtain this information from a reputable source like the official Optimism documentation.

First, you need the correct RPC URL. This is essentially the address your MetaMask wallet will use to communicate with the Optimism network. You can find this on the official Optimism website or trusted community resources. Never use an RPC URL from an untrusted source, as this could compromise your funds.

Once you have the RPC URL, open your MetaMask wallet. Click on the network selection in the top right corner. Usually, it shows "Main Ethereum Network" or similar. Look for an option that says "Add Network" or something similar. The exact wording may vary slightly depending on your MetaMask version.

Now, you'll be presented with a form to input the Optimism network details. You'll need the following information (again, obtain these from a trusted source):

• Network Name: Optimism Mainnet
• New RPC URL: (Paste the URL you obtained earlier)
• Chain ID: 10
• Currency Symbol: OP
• Block Explorer URL: (The URL for Optimism's block explorer)

After entering all the necessary information, click "Save". MetaMask will now add Optimism as a selectable network. You should see "Optimism Mainnet" appear in your network dropdown menu. Selecting it will switch your MetaMask wallet to the Optimism network.

Remember that you'll still interact with Ethereum (Layer 1) to initially bridge funds to Optimism (Layer 2). This bridge transaction will incur gas fees on the Ethereum mainnet. Subsequently, transactions within Optimism will also incur gas fees, but generally at a lower cost than on the Ethereum mainnet. Always ensure you have sufficient ETH in your MetaMask wallet to cover these fees.

Understanding Layer 1 (Ethereum) and Layer 2 (Optimism)

It's crucial to understand that Optimism is a Layer 2 scaling solution built on top of Ethereum. This means transactions are initially processed on Ethereum (Layer 1) before being finalized on Optimism (Layer 2). Therefore, even though you're interacting with Optimism, you'll still need ETH for initial bridging and gas fees on the Ethereum mainnet. Funds are then transferred to your Optimism address, allowing you to transact on the Optimism network with significantly lower fees.

Frequently Asked Questions:

Q: What if I enter the wrong RPC URL?

A: Entering an incorrect RPC URL could prevent your wallet from connecting to Optimism, or worse, potentially lead to the loss of funds. Always double-check the URL against a reputable source like the official Optimism website.

Q: Why are gas fees still involved even though I'm on Optimism?

A: While Optimism significantly reduces gas fees compared to Ethereum, you'll still incur fees for transactions on the Optimism network itself. Additionally, transferring funds from Ethereum (Layer 1) to Optimism (Layer 2) involves a bridging process that requires gas fees on the Ethereum mainnet.

Q: My transactions are failing. What should I do?

A: Double-check that you've correctly added the Optimism network to MetaMask, including the RPC URL, Chain ID, and other details. Ensure you have enough ETH to cover gas fees on both Ethereum and Optimism. If the issue persists, check the Optimism community forums or support channels for assistance.

Q: Can I use any ERC-20 token on Optimism?

A: Not all ERC-20 tokens are available on Optimism. Only tokens that have been bridged to the Optimism network will be usable. You'll need to check if a specific token is supported on Optimism before attempting to transfer it.

Q: Where can I find the most up-to-date information about the Optimism network?

A: The official Optimism website and their documentation are the best places to find the most accurate and up-to-date information about the network, including RPC URLs and other essential details. Always verify information from unofficial sources against the official documentation.