# useIsFetching

`useIsFetching` is an optional hook that returns the `number` of the queries that your application is loading or fetching in the background (useful for app-wide loading indicators).

```js
import { useIsFetching } from 'react-query'
// How many queries are fetching?
const isFetching = useIsFetching()
// How many queries matching the posts prefix are fetching?
const isFetchingPosts = useIsFetching(['posts'])
```

**Options**

- `queryKey?: QueryKey`: [Query Keys](../guides/query-keys)
- `filters?: QueryFilters`: [Query Filters](../guides/filters#query-filters)

**Returns**

- `isFetching: number`
  - Will be the `number` of the queries that your application is currently loading or fetching in the background.