How to Add Custom Networks to MetaMask – RPC Configuration Guide

Adding a custom network to MetaMask requires entering the network name, RPC URL, chain ID, currency symbol, and block explorer URL. Once added, you can receive and send tokens and interact with DApps on that network. To buy tokens on different chains, you can operate on Binance and withdraw to the corresponding network. Download the Binance App (iOS users refer to the iOS installation guide) for convenient cross-chain transfers.

How to Add a Custom Network in MetaMask?

Browser Extension

1. Open MetaMask extension
2. Click the network selector in the top left (defaults to "Ethereum Mainnet")
3. Click "Add Network"
4. MetaMask may offer one-click options for popular networks
5. For manual addition, click "Add a network manually"
6. Fill in these five required fields:
   • Network Name
   • New RPC URL
   • Chain ID
   • Currency Symbol
   • Block Explorer URL
7. Click "Save"

Mobile App

1. Open MetaMask App
2. Tap the menu icon in the top left
3. Go to "Settings" > "Networks"
4. Tap "Add Network"
5. Choose a popular network or enter details manually
6. Save

What Are the RPC Parameters for Popular Networks?

Here are the standard configuration parameters for commonly used networks:

BNB Smart Chain (BSC)

• Network Name: BNB Smart Chain
• RPC URL: https://bsc-dataseed.binance.org
• Chain ID: 56
• Currency Symbol: BNB
• Explorer: https://bscscan.com

Polygon

• Network Name: Polygon Mainnet
• RPC URL: https://polygon-rpc.com
• Chain ID: 137
• Currency Symbol: MATIC
• Explorer: https://polygonscan.com

Arbitrum One

• Network Name: Arbitrum One
• RPC URL: https://arb1.arbitrum.io/rpc
• Chain ID: 42161
• Currency Symbol: ETH
• Explorer: https://arbiscan.io

Optimism

• Network Name: Optimism
• RPC URL: https://mainnet.optimism.io
• Chain ID: 10
• Currency Symbol: ETH
• Explorer: https://optimistic.etherscan.io

Avalanche C-Chain

• Network Name: Avalanche C-Chain
• RPC URL: https://api.avax.network/ext/bc/C/rpc
• Chain ID: 43114
• Currency Symbol: AVAX
• Explorer: https://snowtrace.io

Base

• Network Name: Base
• RPC URL: https://mainnet.base.org
• Chain ID: 8453
• Currency Symbol: ETH
• Explorer: https://basescan.org

What Is an RPC Node? Why Are There Multiple Options?

An RPC (Remote Procedure Call) node is the interface MetaMask uses to communicate with a blockchain network. Each chain typically has multiple RPC providers:

• Official RPC: Maintained by the project team, free but may be congested
• Infura/Alchemy: Professional RPC providers, fast and stable
• Public RPC: Free nodes maintained by the community

Factors to consider when choosing an RPC:

• Speed: Lower latency means faster responses
• Reliability: Major providers offer more stable RPCs
• Privacy: Some RPCs may log your request IP address
• Rate limiting: Free RPCs may have request frequency limits

If the default RPC is slow or frequently errors, switch to another node. Chainlist.org provides RPC lists for each chain.

How to Use Chainlist for One-Click Network Addition?

Chainlist is a convenient tool for one-click network addition to MetaMask:

1. Open chainlist.org
2. Connect your MetaMask wallet
3. Search for the network name
4. Click "Add to MetaMask"
5. Approve in the MetaMask popup
6. Network is automatically added

Chainlist can also help you test RPC node speeds and choose the fastest one.

What Else to Do After Adding a Network?

After adding a new network, you may also need to:

1. Add custom tokens: Tokens on the new network may not display automatically — manually import contract addresses
2. Get gas tokens: Each chain needs its native token for gas (BSC needs BNB, Polygon needs MATIC)
3. Cross-chain transfers: When withdrawing from Binance, select the corresponding network
4. Connect to DApps: Switch to the correct network when accessing DeFi protocols or NFT platforms

FAQ

Will adding a network affect my existing assets?

No. Adding a new network doesn't affect your assets on other networks — it simply expands MetaMask's network list.

Is my balance the same across different networks?

Not necessarily. Although the address is the same (EVM-compatible chains), each chain's balance is independent. Having 1 ETH on Ethereum doesn't mean you have 1 ETH on Arbitrum.

What if I enter the wrong RPC?

MetaMask may fail to connect to the network. You can find the network in "Settings > Networks" and edit or delete it to re-add.

What's the point of adding test networks?

Test networks are used by developers to test DApps and by regular users to practice operations. Tokens on test networks have no real value and can be obtained for free. Common testnets include Goerli and Sepolia.

Why does MetaMask show a security warning for some networks?

MetaMask displays security warnings for unverified custom RPCs. As long as you confirm the RPC source is reliable (e.g., from official documentation or Chainlist), the warning can be disregarded.

Safety Tips

• Only use RPC addresses from official documentation or Chainlist — don't use RPCs from unknown sources
• Malicious RPCs could display fake balances or transaction information
• Verify chain ID and network parameters before adding
• Test with small amounts before operating on a new network
• Ensure MetaMask is from an official source via the Binance App
• Don't share your RPC API keys with others