Overview
Adding Arbitrum to your MetaMask wallet unlocks faster, cheaper transactions while maintaining Ethereum's security. This guide covers both mainnet and testnet configurations using Alchemy's reliable RPC endpoints.
👉 Need a secure wallet for Arbitrum transactions?
Key Steps
- Choose Network Type: Mainnet for real transactions or Sepolia testnet for development
- Create Alchemy Account: Free L2 infrastructure access
- Configure Arbitrum App: Generate API keys
- Network Integration: One-click "Add to Wallet" or manual RPC setup
Mainnet vs. Testnets
Arbitrum offers:
| Network | Use Case | Status |
|--------------|--------------------|-------------|
| Mainnet | Production dApps | Live |
| Sepolia | Testing | Recommended |
| Goerli | Legacy Testing | Deprecated |
Why Sepolia?
- Fully supported by Alchemy
- Free Sepolia faucet available
- Replaces deprecated Goerli network
Endpoints
Mainnet: https://arb-mainnet.g.alchemy.com/v2/YOUR-API-KEY
Sepolia: https://eth-sepolia.g.alchemy.com/v2/YOUR-API-KEY Step-by-Step Setup
1. Create Alchemy Account
- Visit Alchemy
- Select Ethereum + L2 Ecosystem during signup
2. Build Arbitrum App
- Dashboard > Create App > Choose "Arbitrum"
- Specify Mainnet/Sepolia
3. Add Network to MetaMask
Option A: One-Click Method
- Use Alchemy's "Add to Wallet" button
Option B: Manual Configuration
- Open MetaMask > Networks dropdown
- Click "Add Network"
Enter details:
Network Name: Arbitrum RPC URL: [Your Alchemy HTTP] ChainID: 42161 (Mainnet) / 421613 (Testnet) Currency Symbol: ETH Block Explorer: https://arbiscan.io
FAQ
Q: Why use Alchemy's RPC?
A: Guaranteed uptime and enhanced performance compared to public endpoints.
Q: Can I use Arbitrum without MetaMask?
A: Yes, but MetaMask provides the most seamless L2 experience.
👉 Explore advanced Arbitrum features here
Pro Tips
- Always verify RPC URLs
- Bookmark Arbiscan for transaction checks
- Use Sepolia for cost-free testing