VueUse is a collection of composables for common tasks: browser APIs, sensors, state, animations, network, and more. Instead of writing your own useLocalStorage or useDebounceFn from scratch, you install @vueuse/core and get 200+ battle-tested composables that work with Vue 3's reactivity system.

npm install @vueuse/core

Most useful composables by category

Browser and DOM

useLocalStorage / useSessionStorage: reactive storage that syncs automatically.

const theme = useLocalStorage('theme', 'light')
theme.value = 'dark' // saved to localStorage immediately

useClipboard: copy to clipboard.

const { copy, copied } = useClipboard()
await copy('Hello!')
// copied.value is true for 1.5 seconds

useMediaQuery: reactive CSS media query.

const isMobile = useMediaQuery('(max-width: 768px)')

useDark: dark mode with persistence.

const isDark = useDark()
const toggle = useToggle(isDark)

useEventListener: auto-cleaned event listeners.

useEventListener(window, 'resize', () => {
  console.log(window.innerWidth)
})
// listener removed automatically when component unmounts

State

useToggle: boolean toggle.

const [value, toggle] = useToggle(false)
toggle() // true
toggle() // false

useDebounceFn / useThrottleFn: debounce and throttle.

const search = useDebounceFn((query: string) => {
  fetchResults(query)
}, 300)

createGlobalState: shared state across components without Pinia.

const useGlobalCounter = createGlobalState(() => {
  const count = ref(0)
  return { count }
})

Network

useFetch: reactive fetch wrapper (different from Nuxt's useFetch).

const { data, error, isFetching } = useFetch('https://api.example.com/posts')
  .get()
  .json<Post[]>()

useWebSocket: reactive WebSocket connection.

const { data, send, status } = useWebSocket('wss://example.com/ws')

watch(data, (message) => {
  console.log('Received:', message)
})

Sensors

useMouse: reactive mouse position.

const { x, y } = useMouse()

useIntersectionObserver: detect element visibility.

const target = ref<HTMLElement>()
const isVisible = ref(false)

useIntersectionObserver(target, ([entry]) => {
  isVisible.value = entry.isIntersecting
})

useElementSize: reactive element dimensions.

const el = ref<HTMLElement>()
const { width, height } = useElementSize(el)

Utilities

watchDebounced: debounced watcher.

const search = ref('')

watchDebounced(search, (value) => {
  fetchResults(value)
}, { debounce: 300 })

whenever: watch that fires only when value is truthy.

const isReady = ref(false)

whenever(isReady, () => {
  console.log('Ready!')
})

useAsyncState: run async function with reactive loading/error state.

const { state, isLoading, error } = useAsyncState(
  () => fetch('/api/user').then(r => r.json()),
  null // initial state
)

Using in a real component

<script setup>
import { useLocalStorage, useDebounceFn, useMediaQuery } from '@vueuse/core'

const searchQuery = useLocalStorage('search', '')
const isMobile = useMediaQuery('(max-width: 768px)')

const debouncedSearch = useDebounceFn((query: string) => {
  fetchResults(query)
}, 300)

watch(searchQuery, (q) => debouncedSearch(q))
</script>

<template>
  <input v-model="searchQuery" :placeholder="isMobile ? 'Search...' : 'Search articles...'" />
</template>

VueUse vs writing your own

Write your own composable when the logic is specific to your domain. Use VueUse when the problem is generic (debounce, storage, media queries, clipboard, intersection observer). VueUse composables handle edge cases, SSR compatibility, and cleanup that you would otherwise have to implement yourself.