# onlineManager

```ts
const onlineManager: OnlineManager;
```

Defined in: [packages/query-core/src/onlineManager.ts:117](https://github.com/TanStack/query/blob/main/packages/query-core/src/onlineManager.ts#L117)

Singleton instance of [OnlineManager](../interfaces/OnlineManager.md), used to manage and observe the online state within TanStack Query.