You add a network to MetaMask by entering a valid RPC URL, Chain ID, and network details in the “Add Network” settings — MetaMask connects to blockchain nodes through RPC endpoints.
This enables Web3 access across Ethereum, BNB Chain, Polygon, and other EVM-compatible chains.
Click it at the top center of the MetaMask extension.
Then click “Add a network manually.”
Fill in the network name, symbol, and block explorer.
The network is now available in your selector.
Open the MetaMask app → tap menu → Settings → Networks → Add Network → enter network credentials → tap Save.
| Parameter | Description | Example (BSC) |
|---|---|---|
| Network Name | User-defined blockchain name | BNB Smart Chain |
| RPC URL | Node endpoint for blockchain access | https://bsc-dataseed.binance.org |
| Chain ID | Unique blockchain identifier | 56 |
| Currency Symbol | Native token ticker | BNB |
| Block Explorer | Transaction explorer URL | https://bscscan.com |
MetaMask validates Chain ID uniqueness before saving to prevent network conflicts.
| Network | RPC URL | Chain ID | Symbol |
|---|---|---|---|
| Binance Smart Chain | https://bsc-dataseed.binance.org | 56 | BNB |
| Polygon Mainnet | https://polygon-rpc.com | 137 | MATIC |
| Ethereum Sepolia Testnet | Infura or public RPC providers | 11155111 | ETH |
| Network | Typical Gas Fee | Use Case |
|---|---|---|
| Ethereum Mainnet | $5–$50 (can exceed $100) | High-value DeFi, NFTs |
| Polygon | <$0.01 | Microtransactions, gaming |
| BSC | ~$0.05–$0.30 | Trading, DeFi, staking |
Only Use Trusted RPC SourcesMalicious RPC endpoints can log requests. Always verify the Chain ID and explorer URL against official project documentation.
An RPC URL is a gateway connecting MetaMask to blockchain nodes. Infura provides Ethereum RPC endpoints, public RPCs offer free but rate-limited access, and private RPCs improve speed and reliability. Incorrect RPC URLs cause transaction failures.
| Error | Cause |
|---|---|
| Network conflict | Wrong Chain ID entered |
| Connection failure or timeout | Invalid RPC URL |
| Reduced transaction visibility | Missing block explorer |
| Network not switching | Cached state or UI sync issue |
Fix by re-entering the correct RPC URL, Chain ID, and symbol, verifying details against official documentation, and restarting the extension or app if the issue persists.
| Type | Purpose | Token Value |
|---|---|---|
| Mainnet | Real transactions | Real value |
| Testnet | Development/testing | No real value |
Open the network dropdown, select “Add network” → “Add a network manually,” and enter the RPC URL, Chain ID, currency symbol, and block explorer URL.
Yes, if you use trusted RPC sources. MetaMask never exposes your private key when adding a network, but malicious RPC endpoints can log your requests.
This usually happens when the Chain ID entered doesn’t match the network, or conflicts with an already-added network.
Yes, dApps can trigger a wallet_addEthereumChain request, which you approve, and MetaMask saves the configuration automatically.
