eth_chainId

Returns the chain ID of the current network. For Linea mainnet, this returns 0xe708 (59144 in decimal).

Parameters

None

Returns

QUANTITY - The chain ID as a hexadecimal string.

Request Example

{
  "jsonrpc": "2.0",
  "method": "eth_chainId",
  "params": [],
  "id": 1
}

Response Example

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0xe708"
}

Implementation Examples

JavaScript

import { JsonRpcProvider } from 'ethers';

const provider = new JsonRpcProvider('https://api-linea-mainnet-archive.n.dwellir.com/YOUR_API_KEY');

// Get chain ID
async function getChainId() {
  const chainId = await provider.getNetwork().then(n => n.chainId);
  
  console.log('Chain ID (decimal):', chainId);
  console.log('Chain ID (hex):', '0x' + chainId.toString(16));
  
  // Verify it's Linea
  if (chainId === 59144n) {
    console.log('Connected to Linea mainnet');
  }
  
  return chainId;
}

// Verify network before transactions
async function verifyNetwork() {
  const chainId = await provider.send('eth_chainId', []);
  const expectedChainId = '0xe708'; // Linea mainnet
  
  if (chainId !== expectedChainId) {
    throw new Error(`Wrong network! Expected Linea (${expectedChainId}), got ${chainId}`);
  }
  
  return true;
}

Python

from web3 import Web3

w3 = Web3(Web3.HTTPProvider('https://api-linea-mainnet-archive.n.dwellir.com/YOUR_API_KEY'))

def get_chain_id():
    """Get the chain ID"""
    
    chain_id = w3.eth.chain_id
    
    print(f"Chain ID (decimal): {chain_id}")
    print(f"Chain ID (hex): {hex(chain_id)}")
    
    # Verify it's Linea
    if chain_id == 59144:
        print("Connected to Linea mainnet")
    else:
        print(f"Connected to unknown network: {chain_id}")
    
    return chain_id

def verify_network():
    """Verify connected to correct network"""
    
    chain_id = w3.eth.chain_id
    expected = 59144  # Linea mainnet
    
    if chain_id != expected:
        raise ValueError(f"Wrong network! Expected {expected}, got {chain_id}")
    
    return True

Network Information

Network	Chain ID (Decimal)	Chain ID (Hex)
Linea Mainnet	59144	0xe708

Common Use Cases

1. Multi-Network Support

// Handle multiple networks
async function getNetworkConfig() {
  const chainId = await provider.send('eth_chainId', []);
  
  const networks = {
    '0x1': { name: 'Ethereum Mainnet', explorer: 'https://etherscan.io' },
    '0xe708': { name: 'Linea Mainnet', explorer: 'https://lineascan.build' },
    '0x89': { name: 'Polygon', explorer: 'https://polygonscan.com' }
  };
  
  const network = networks[chainId] || { name: 'Unknown', explorer: null };
  
  return {
    chainId: chainId,
    decimal: parseInt(chainId, 16),
    ...network
  };
}

2. Wallet Connection Validation

// Validate wallet is on correct network
async function validateWalletNetwork(expectedChainId = 59144) {
  if (typeof window.ethereum === 'undefined') {
    throw new Error('No wallet detected');
  }
  
  const chainId = await window.ethereum.request({ 
    method: 'eth_chainId' 
  });
  
  const currentChainId = parseInt(chainId, 16);
  
  if (currentChainId !== expectedChainId) {
    // Request network switch
    try {
      await window.ethereum.request({
        method: 'wallet_switchEthereumChain',
        params: [{ chainId: '0xe708' }]
      });
    } catch (switchError) {
      // Network not added to wallet
      if (switchError.code === 4902) {
        await addLineaNetwork();
      }
    }
  }
}

// Add Linea network to wallet
async function addLineaNetwork() {
  await window.ethereum.request({
    method: 'wallet_addEthereumChain',
    params: [{
      chainId: '0xe708',
      chainName: 'Linea',
      nativeCurrency: {
        name: 'ETH',
        symbol: 'ETH',
        decimals: 18
      },
      rpcUrls: ['https://api-linea-mainnet-archive.n.dwellir.com/YOUR_API_KEY'],
      blockExplorerUrls: ['https://lineascan.build']
    }]
  });
}

Need help? Contact our support team or check the Linea documentation.