> For the complete documentation index, see [llms.txt](https://docs.fortmatic.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fortmatic.com/v1.x/web3-integration/network-configuration.md).

# Network Configuration

## Switch Network on Testnet

On Testnet, you can switch between Rinkeby, Ropsten, and Kovan. Default is Rinkeby.

```javascript
import Fortmatic from 'fortmatic';
import Web3 from 'web3';

// Default is Rinkeby
const fm = new Fortmatic('YOUR_TEST_API_KEY');
window.web3 = new Web3(fm.getProvider());

// Setting testnet network to Ropsten
const fm = new Fortmatic('YOUR_TEST_API_KEY', 'ropsten');
window.web3 = new Web3(fm.getProvider());

// Setting testnet network to Kovan
const fm = new Fortmatic('YOUR_TEST_API_KEY', 'kovan');
window.web3 = new Web3(fm.getProvider());
```

## Switch Network to Custom Node

You can choose to use your own node, like a development test node or a sidechain. We currently support: 

* [Matic](https://matic.network/) : node url under `matic.com` domain
  * Testnet URL: [https://testnet2.matic.network](https://testnet2.matic.network/)
  * Mainnet URL: <https://alpha.ethereum.matic.network>
* [Skale](https://skale.network/): node url under `skalenode.com` domain
  * Get started with requesting a Skale node:\
    <https://skale.network/docs/developers/getting-started/beginner>
* Localhost: node url with `localhost` or `127.0.0.1`

Please contact us at [our support channel](https://t.me/fortmatic) if you want to use other nodes.

```javascript
import Fortmatic from 'fortmatic';
import Web3 from 'web3';

const customNodeOptions = {
    rpcUrl: 'http://127.0.0.1:7545', // your own node url
    chainId: 1011 // chainId of your own node
}

// Setting network to localhost blockchain
const fm = new Fortmatic('YOUR_TEST_API_KEY', customNodeOptions);
window.web3 = new Web3(fm.getProvider());
```

##


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