POST
/
4ab982aa70a7baead515ffdb5915df3f
curl --request POST \
  --url https://fantom-mainnet.core.chainstack.com/4ab982aa70a7baead515ffdb5915df3f \
  --header 'Content-Type: application/json' \
  --data '{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "eth_chainId",
  "params": []
}'
{
  "jsonrpc": "<string>",
  "id": 123,
  "result": "<string>"
}

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

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();

​
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.

Body

application/json
​
id
integer
default:1
​
jsonrpc
string
default:2.0
​
method
string
default:eth_chainId
​
params
any[]

Response

200 - application/json
The network Chain ID
​
jsonrpc
string
​
id
integer
​
result
string