eth_chainId

Get ChainId

POSThttps://site1.moralis-nodes.com/:chain/:apiKey

Returns the current chain ID, identifying the current blockchain. The chain ID is a unique identifier for each blockchain and is used for transaction signing to prevent replay attacks across chains.

Note

Please refer to RPC schema page for more details on the RPC params and RPC response definitions of the RPC method.

PATH PARAMS

chainstringrequired

The blockchain to interact with.

ethsepoliaholeskybasebase-sepoliapolygonamoybscbsc-testnetarbitrumarbitrum-sepoliaoptimismoptimism-sepoliagnosisgnosis-testnetlinealinea-sepoliaavalanchemoonbeammoonrivermoonbaseblastblast-sepoliamantlemantle-sepoliapolygon-zkevmpolygon-zkevm-cardonazksynczksync-sepoliazetachainzetachain-testnetfantomopbnbflowflow-testnetroninronin-testnetlisklisk-sepoliapulse

apiKeystringrequired

Your API key for authentication.

BODY PARAM

Request Bodyobjectrequired

The request payload for the eth_chainId method.

{ "jsonrpc": "2.0", "id": 1, "method": "eth_chainId" }

Responses

200Returns the chain ID of the current blockchain.

400Bad Request

404Not Found

429Too Many Requests

500Internal Server Error

cURL

curl --request POST \
     --url 'https://site1.moralis-nodes.com/eth/YOUR_API_KEY' \
     --header 'accept: application/json' \
     --header 'content-type: application/json' \
     --data '
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_chainId"
}
'

Node.js

// Node.js v18+ has native fetch support
// No additional dependencies required

const options = {
  method: 'POST',
  headers: {
    accept: 'application/json',
    'content-type': 'application/json'
  },
  body: JSON.stringify({
    "jsonrpc": "2.0",
    "id": 1,
    "method": "eth_chainId"
  })
};

fetch('https://site1.moralis-nodes.com/eth/YOUR_API_KEY', options)
  .then(response => response.json())
  .then(response => console.log(response))
  .catch(err => console.error(err));

Python

# Dependencies to install:
# $ python -m pip install requests

import requests

url = "https://site1.moralis-nodes.com/eth/YOUR_API_KEY"

payload = {
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_chainId"
}
headers = {
  "Accept": "application/json",
  "Content-Type": "application/json"
}

response = requests.request("POST", url, json=payload, headers=headers)

print(response.text)

Go

package main

import (
  "fmt"
  "strings"
  "net/http"
  "io"
)

func main() {

  url := "https://site1.moralis-nodes.com/eth/YOUR_API_KEY"

  payload := strings.NewReader("{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"eth_chainId\"}")

  req, _ := http.NewRequest("POST", url, payload)

  req.Header.Add("Accept", "application/json")
  req.Header.Add("Content-Type", "application/json")

  res, _ := http.DefaultClient.Do(req)

  defer res.Body.Close()
  body, _ := io.ReadAll(res.Body)

  fmt.Println(res)
  fmt.Println(string(body))

}

PHP

<?php
// Dependencies to install:
// $ composer require guzzlehttp/guzzle

require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://site1.moralis-nodes.com/eth/YOUR_API_KEY', [
  'body' => '{"jsonrpc":"2.0","id":1,"method":"eth_chainId"}',
  'headers' => [
    'Accept' => 'application/json',
    'Content-Type' => 'application/json',
  ],
]);

echo $response->getBody();

Response Example

200 Returns the chain ID of the current blockchain.

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x1"
}