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title Node.js Quickstart - MetaMask Connect EVM
description Set up MetaMask Connect EVM in a Node.js application with createEVMClient, connect via QR code, and use the EIP-1193 provider for JSON-RPC requests.
sidebar_label Node.js
keywords
connect
MetaMask
Node.js
SDK
CLI
server-side
createEVMClient
EIP-1193
QR code
personal_sign
node quickstart

Connect to EVM - Node.js quickstart

Get started with MetaMask Connect EVM in a Node.js application. The SDK displays a QR code in the terminal that you scan with the MetaMask mobile app to establish a connection.

:::info No polyfills required Node.js has native support for Buffer, crypto, stream, and other modules that require polyfilling in browser or React Native environments. :::

Prerequisites

Steps

1. Install MetaMask Connect EVM

Install the EVM client in an existing Node.js project:

npm install @metamask/connect-evm

2. Initialize MetaMask Connect EVM

Create a file (index.mjs) and initialize the client using createEVMClient. In Node.js, there is no window.location, so you must set dapp.url explicitly:

import { createEVMClient, getInfuraRpcUrls } from '@metamask/connect-evm'

const evmClient = await createEVMClient({
  dapp: {
    name: 'My Node.js App',
    url: 'https://myapp.com',
  },
  api: {
    supportedNetworks: getInfuraRpcUrls({
      infuraApiKey: 'YOUR_INFURA_API_KEY',
    }),
  },
})

:::info Async client createEVMClient returns a promise. Always await it before using the client. :::

3. Connect to MetaMask

Call connect to start the connection flow. A QR code appears in the terminal. Scan it with the MetaMask mobile app:

try {
  const { accounts, chainId } = await evmClient.connect({
    chainIds: ['0x1'],
  })
  console.log('Connected account:', accounts[0])
  console.log('Active chain:', chainId)
} catch (error) {
  if (error.code === 4001) {
    console.log('User rejected the connection request')
  } else if (error.code === -32002) {
    console.log('Connection request already pending')
  } else {
    console.error('Connection failed:', error)
  }
}

4. Use the provider

Get the EIP-1193 provider and make JSON-RPC requests:

const provider = evmClient.getProvider()

const balance = await provider.request({
  method: 'eth_getBalance',
  params: [accounts[0], 'latest'],
})
console.log('Balance (wei):', balance)

5. Sign a message

Use personal_sign to request a signature from the connected wallet:

const message = '0x' + Buffer.from('Hello from Node.js!', 'utf8').toString('hex')

const signature = await provider.request({
  method: 'personal_sign',
  params: [message, accounts[0]],
})
console.log('Signature:', signature)

6. Disconnect

await evmClient.disconnect()
console.log('Disconnected')

Listen for events

Use eventHandlers in the client configuration to react to connection state changes:

const evmClient = await createEVMClient({
  dapp: {
    name: 'My Node.js App',
    url: 'https://myapp.com',
  },
  api: {
    supportedNetworks: getInfuraRpcUrls({
      infuraApiKey: 'YOUR_INFURA_API_KEY',
    }),
  },
  eventHandlers: {
    connect: ({ accounts, chainId }) => {
      console.log('Connected:', accounts, 'on chain', chainId)
    },
    disconnect: () => {
      console.log('Disconnected')
    },
    accountsChanged: accounts => {
      console.log('Accounts changed:', accounts)
    },
    chainChanged: chainId => {
      console.log('Chain changed:', chainId)
    },
  },
})

Full example

import { createEVMClient, getInfuraRpcUrls } from '@metamask/connect-evm'

const evmClient = await createEVMClient({
  dapp: {
    name: 'My Node.js App',
    url: 'https://myapp.com',
  },
  api: {
    supportedNetworks: getInfuraRpcUrls({
      infuraApiKey: 'YOUR_INFURA_API_KEY',
    }),
  },
})

// Connect — scan the QR code with the MetaMask mobile app
const { accounts, chainId } = await evmClient.connect({ chainIds: ['0x1'] })
console.log('Connected:', accounts[0], 'on', chainId)

// Get balance
const provider = evmClient.getProvider()
const balance = await provider.request({
  method: 'eth_getBalance',
  params: [accounts[0], 'latest'],
})
console.log('Balance:', balance)

// Sign a message
const message = '0x' + Buffer.from('Hello from Node.js!', 'utf8').toString('hex')
const signature = await provider.request({
  method: 'personal_sign',
  params: [message, accounts[0]],
})
console.log('Signature:', signature)

// Disconnect
await evmClient.disconnect()
console.log('Disconnected')

Run it with:

node index.mjs

Next steps