net_version | Celo RPC Docs

Get the current network ID on Celo. Useful for endpoint identification and multi-network routing.

Returns the current network ID on Celo as a decimal string. The network ID identifies which network the node is connected to.

Why Celo? Build on the mobile-first L2 powering 500K+ daily active users and $2B+ monthly stablecoin volume with phone number-based addressing, sub-cent fees, 150+ country adoption, Nightfall privacy layer, and Opera browser integration.

When to Use This Method

net_version is essential for mobile payment developers, fintech builders, and teams targeting emerging markets:

Endpoint Identification - Confirm your application is connected to the expected Celo network
Multi-Chain App Routing - Dynamically detect which network an RPC endpoint serves and route logic accordingly
Connection Validation - Perform a quick sanity check during node or provider initialization

Code Examples

Common Use Cases

1. Multi-Chain Connection Validator

Verify your application connects to the expected network before processing any transactions:

JavaScript

const EXPECTED_NETWORKS = {
  '1': 'Ethereum Mainnet',
  '137': 'Polygon',
  '42161': 'Arbitrum One',
  '10': 'Optimism',
};

async function validateNetwork(provider, expectedNetworkId) {
  const networkId = await provider.send('net_version', []);

  if (networkId !== expectedNetworkId) {
    const actual = EXPECTED_NETWORKS[networkId] || `Unknown (${networkId})`;
    const expected = EXPECTED_NETWORKS[expectedNetworkId] || expectedNetworkId;
    throw new Error(`Wrong network: connected to ${actual}, expected ${expected}`);
  }

  console.log(`Connected to ${EXPECTED_NETWORKS[networkId]}`);
  return networkId;
}

2. Dynamic Chain Router

Route application logic based on the detected network:

JavaScript

async function createChainRouter(rpcUrl) {
  const provider = new JsonRpcProvider(rpcUrl);
  const networkId = await provider.send('net_version', []);

  const config = {
    '1': { explorer: 'https://etherscan.io', confirmations: 12 },
    '137': { explorer: 'https://polygonscan.com', confirmations: 128 },
    '42161': { explorer: 'https://arbiscan.io', confirmations: 1 },
  };

  if (!config[networkId]) {
    throw new Error(`Unsupported network ID: ${networkId}`);
  }

  return { provider, networkId, ...config[networkId] };
}

3. Network ID vs Chain ID Comparison

Compare net_version with eth_chainId when you need both endpoint identity and signing context:

Python

from web3 import Web3

def verify_chain_identity(rpc_url):
    w3 = Web3(Web3.HTTPProvider(rpc_url))

    network_id = int(w3.net.version)
    chain_id = w3.eth.chain_id

    if network_id != chain_id:
        print(f'Network ID ({network_id}) differs from chain ID ({chain_id})')
    else:
        print(f'Network and chain ID match: {chain_id}')

    print('Use eth_chainId as the signing source of truth')

    return {'network_id': network_id, 'chain_id': chain_id}

Best Practices

Use eth_chainId for transaction signing (EIP-155 replay protection) -- net_version is for network identification only
Cache the network ID at startup -- it does not change during a session
Some L2 and sidechain networks share the same network ID as their L1 -- always combine with eth_chainId for unambiguous identification
For multi-chain dApps, maintain a mapping of network IDs to chain-specific contract addresses and RPC endpoints
The net_* namespace may be disabled on some node configurations -- handle the -32601 error gracefully

Error Handling

Error Code	Description	Solution
-32601	Method not found	The node may have the `net` namespace disabled -- check node startup flags
-32603	Internal error	Node may be starting up -- retry after delay
-32005	Rate limit exceeded	Reduce polling frequency or implement backoff

eth_chainId - Get the EIP-155 chain ID (preferred for transaction signing)
net_listening - Check whether the client reports peer-listening state
net_peerCount - Get number of connected peers
eth_syncing - Check node sync progress

net_version - Celo RPC Method