​
Custom networks

If you cannot find the network you are looking for within the @reown/appkit/networks path, you can always add a custom network. Since AppKit v1.1.0, there are two ways to add your network to AppKit: Reown AppKit use Viem to provide EVM chains to users under the hood. If your chain is EVM-compatible, it is recommended to open a PR to Viem to add your network to Viem’s directory. Once your chain is accepted by Viem, it will automatically be available in AppKit with no additional steps required. Here is the documentation of how to add new chain to Viem: https://github.com/wevm/viem/blob/main/.github/CONTRIBUTING.md#chains

​
2. Creating a Custom Chain Object

You can also create a custom network object without waiting for approval from Viem’s repository. Required Information You will need the following values to create a custom network:
  • id: Chain ID of the network.
  • name: Name of the network.
  • caipNetworkId: CAIP-2 compliant network ID.
  • chainNamespace: Chain namespace.
  • nativeCurrency: Native currency of the network.
  • rpcUrls: Object containing the RPC URLs for the network.
  • blockExplorers: Object containing the block explorers for the network.
import { defineChain } from '@reown/appkit/networks';

// Define the custom network
const customNetwork = defineChain({
  id: 123456789,
  caipNetworkId: 'eip155:123456789',
  chainNamespace: 'eip155',
  name: 'Custom Network',
  nativeCurrency: {
    decimals: 18,
    name: 'Ether',
    symbol: 'ETH',
  },
  blockExplorers: {
    default: { name: 'Explorer', url: 'BLOCK_EXPLORER_URL' },
  },
  contracts: {
    // Add the contracts here
  }
})

// Then pass it to the AppKit
createAppKit({
    adapters: [...],
    networks: [customNetwork],
    chainImages: { // Customize networks' logos
      123456789: '/custom-network-logo.png', // <chainId>: 'www.network.com/logo.png'
    }
})
You can use your own RPC by setting the customRpcUrls option in the AppKit configuration. This lets you define custom RPC URLs for specific chains. Each entry must follow the format: 
customRpcUrls: {
  [eip155:1]: 'https://your.custom.rpc.url',
  [eip155:137]: 'https://your.polygon.rpc.url'
}
AppKit will prioritize these URLs over the default ones.