net_version - Ethereum

Example code for the net_version JSON RPC method. Сomplete guide on how to use net_version JSON RPC in GetBlock Web3 documentation.

This method returns the current network ID as a decimal string. For Ethereum mainnet the value is "1". Network ID historically distinguished chains before the eth_chainId method was standardized; modern applications generally prefer eth_chainId for chain-selection logic.

Parameters

This method takes no parameters.

Request

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "net_version",
    "params": [],
    "id": "getblock.io"
}'

Axios

example.js

const axios = require('axios');

const response = await axios.post('https://go.getblock.io/<ACCESS-TOKEN>/', {
    jsonrpc: '2.0',
    method: 'net_version',
    params: [],
    id: 'getblock.io'
}, {
    headers: { 'Content-Type': 'application/json' }
});

console.log(response.data.result);

Request

example.py

import requests

response = requests.post(
    'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers={'Content-Type': 'application/json'},
    json={
        'jsonrpc': '2.0',
        'method': 'net_version',
        'params': [],
        'id': 'getblock.io'
    }
)

print(response.json())

Rust

example.rs

use reqwest::Client;
use serde_json::{json, Value};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();
    
    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&json!({
            "jsonrpc": "2.0",
            "method": "net_version",
            "params": [],
            "id": "getblock.io"
        }))
        .send()
        .await?
        .json::<Value>()
        .await?;
    
    println!("Result: {}", response["result"]);
    Ok(())
}

Response

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "1"
}

Response Parameters

Parameter	Type	Description
jsonrpc	string	JSON-RPC protocol version ("2.0")
id	string	Request identifier matching the request
result	string	Network ID as a decimal string ("1" for Ethereum mainnet, "11155111" for Sepolia, "560048" for Hoodi)

Use Cases

• Legacy Chain Detection: Support older tooling that predates eth_chainId standardization

• Cross-Reference Verification: Sanity-check that net_version and eth_chainId agree (they generally do on Ethereum-derived chains)

• Endpoint Environment Discovery: Detect whether an endpoint points to mainnet vs a testnet without knowing in advance

• Multi-Chain Dashboards: Display the network name in an administrative UI by looking up the ID

Error Handling

Error Code	Message	Description
-32603	Internal error	Node failed to determine its network ID

Web3 Integration

Ethers.js

ethers-example.js

import { ethers } from 'ethers';

const provider = new ethers.JsonRpcProvider('https://go.getblock.io/<ACCESS-TOKEN>/');

// Modern approach — prefer getNetwork() which returns rich network info:
const network = await provider.getNetwork();
console.log('Chain ID:', network.chainId.toString());
console.log('Name:', network.name);

// Raw net_version if specifically needed:
const netVersion = await provider.send('net_version', []);
console.log('Network ID:', netVersion);

Viem

viem-example.js

import { createPublicClient, http } from 'viem';
import { mainnet } from 'viem/chains';

const client = createPublicClient({
    chain: mainnet,
    transport: http('https://go.getblock.io/<ACCESS-TOKEN>/'),
});

// Modern approach — prefer getChainId (uses eth_chainId under the hood):
const chainId = await client.getChainId();
console.log('Chain ID:', chainId);

// Raw net_version if specifically needed:
const netVersion = await client.request({ method: 'net_version' });
console.log('Network ID:', netVersion);