eth_chainId | Fantom

Fantom API method that returns the current chain ID. Chain ID is used to sign replay-protected transactions and verify whether a network is the desired one. It was introduced in EIP-155.

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Parameters

• none

Response

• quantity — EIP-155 Chain ID

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Use the Chainstack EVM Knife to convert the Chain ID from Hexadecimal to Decimal.

eth_chainId code examples

const { Web3 } = require("web3");
const NODE_URL = "CHAINSTACK_NODE_URL";
const web3 = new Web3(NODE_URL);

async function getChainId() {
  const chain = await web3.eth.getChainId();
  console.log(chain);
}

getChainId();

const ethers = require('ethers');
const NODE_URL = "CHAINSTACK_NODE_URL";
const provider = new ethers.JsonRpcProvider(NODE_URL);

const chainId = async () => {

    // This will return the value in Hex
    const chainId = await provider.send("eth_chainId");
    console.log(`Hex Chain ID: ${chainId}`);
  };

chainId();

from web3 import Web3  
node_url = "CHAINSTACK_NODE_URL"

web3 = Web3(Web3.HTTPProvider(node_url)) 
print(web3.eth.chain_id)  

Use case

One possible use case for the eth_chainId method is to determine which chain a user is connected to when using a DApp with the MetaMask browser extension. This can be useful to provide a customized user experience based on the specific chain that the user is interacting with.

Try the eth_chainId RPC method yourself