> For the complete documentation index, see [llms.txt](https://docs.chainrpc.io/chainrpc/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.chainrpc.io/chainrpc/networks/arbitrum/how-to/choose-a-network.md).

# Choose a network

Use one of these endpoints as your Arbitrum client provider.

{% hint style="warning" %}
**Deprecation warning** 

The Arbitrum Rinkeby testnet is deprecated from the chainRPC API.We recommend users migrate to Arbitrum Goerli to test deployments.Ensure that you replace `API-KEY` with an API key from your [chainRPC dashboard](https://chainrpc.io/dashboard). You must enable the [Arbitrum network add-on](https://docs.infura.io/infura/networks/ethereum/how-to/add-a-network-add-on) to use the endpoints.
{% endhint %}

<table><thead><tr><th width="191.33333333333331">Network</th><th width="245">Description</th><th>URL</th></tr></thead><tbody><tr><td>Arbitrum Mainnet</td><td>JSON-RPC over HTTPS</td><td>https://arb.chainrpc.io/v3/API-KEY</td></tr></tbody></table>


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