🤖 Powerful asynchronous state management, server-state utilities and data fetching for the web. TS/JS, React Query, Solid Query, Svelte Query and Vue Query.
---
id: useIsMutating
title: useIsMutating
`useIsMutating` is an optional hook that returns the `number` of mutations that your application is fetching (useful for app-wide loading indicators).
```tsx
import { useIsMutating } from '@tanstack/react-query'
// How many mutations are fetching?
const isMutating = useIsMutating()
// How many mutations matching the posts prefix are fetching?
const isMutatingPosts = useIsMutating({ mutationKey: ['posts'] })
```
**Options**
- `filters?: MutationFilters`: [Mutation Filters](../../../../framework/react/guides/filters#mutation-filters)
- `context?: React.Context<QueryClient | undefined>`
- Use this to use a custom React Query context. Otherwise, `defaultContext` will be used.
**Returns**
- `isMutating: number`
- Will be the `number` of the mutations that your application is currently fetching.
