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# useApi

A hook to get an ApiPromise and WsProvider instance for a given chain. These instances have chain-specific RPC urls defined and will automatically update when you change your configuration or set a new default RPC for a chain. This hook is used in many **useink** hooks.

```javascript
import { useApi } from 'useink';

export const Api = ({ children }) => {
  const { api } = useApi(); // Get the api instance for the default chain set in UseInkProvider
  const alephApi = useApi('aleph'); // This assumes that 'aleph' config is added to UseInkProvider

  console.log('default chain api', api)
  console.log('aleph chain api', alephApi.api)

  return <h1>Check the console logs...</h1>
}
```

### Return Type[​](https://use.ink/frontend/react/hooks/substrate/use-api#return-type) <a href="#return-type" id="return-type"></a>

```javascript
{
  api: ApiPromise;
  provider: WsProvider;
} | undefined
```


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