Nuxt/docs/2.guide/2.directory-structure/1.components.md
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---
navigation.icon: IconDirectory
title: "components"
description: "The components/ directory is where you put all your Vue components."
head.title: "components/"
---
# Components Directory
The `components/` directory is where you put all your Vue components which can then be imported inside your pages or other components ([learn more](https://vuejs.org/guide/essentials/component-basics.html#components-basics)).
Nuxt automatically imports any components in your `components/` directory (along with components that are registered by any modules you may be using).
```bash
| components/
--| TheHeader.vue
--| TheFooter.vue
```
```html{}[layouts/default.vue]
<template>
<div>
<TheHeader />
<slot />
<TheFooter />
</div>
</template>
```
## Component extensions
By default, any file with an extension specified in the [extensions key of `nuxt.config.ts`](/api/configuration/nuxt-config#extensions) is treated as a component.
If you need to restrict the file extensions that should be registered as components, you can use the extended form of the components directory declaration and its `extensions` key:
```diff
export default defineNuxtModule({
components: [
{
path: '~/components',
+ extensions: ['.vue'],
}
]
})
```
## Component Names
If you have a component in nested directories such as:
```bash
| components/
--| base/
----| foo/
------| Button.vue
```
... then the component's name will be based on its own path directory and filename, with duplicate segments being removed. Therefore, the component's name will be:
```html
<BaseFooButton />
```
::alert
For clarity, we recommend that the component's filename matches its name. (So, in the example above, you could rename `Button.vue` to be `BaseFooButton.vue`.)
::
If you want to auto-import components based only on its name, not path, then you need to set `pathPrefix` option to `false` using extended form of the configuration object:
```diff
export default defineNuxtConfig({
components: [
{
path: '~/components/',
+ pathPrefix: false,
},
],
});
```
This registers the components using the same strategy as used in Nuxt 2. For example, `~/components/Some/MyComponent.vue` will be usable as `<MyComponent>` and not `<SomeMyComponent>`.
## Dynamic Components
If you want to use the Vue `<component :is="someComputedComponent">` syntax, then you will need to use the `resolveComponent` helper provided by Vue.
For example:
```vue
<template>
<component :is="clickable ? MyButton : 'div'" />
</template>
<script setup>
const MyButton = resolveComponent('MyButton')
</script>
```
::alert{type=warning}
If you are using `resolveComponent` to handle dynamic components, make sure not to insert anything but the name of the component, which must be a string and not a variable.
::
Alternatively, though not recommended, you can register all your components globally, which will create async chunks for all your components and make them available throughout your application.
```diff
export default defineNuxtConfig({
components: {
+ global: true,
+ dirs: ['~/components']
},
})
```
You can also selectively register some components globally by placing them in a `~/components/global` directory.
::alert{type=info}
The `global` option can also be set per component directory.
::
## Dynamic Imports
To dynamically import a component (also known as lazy-loading a component) all you need to do is add the `Lazy` prefix to the component's name.
```html{}[layouts/default.vue]
<template>
<div>
<TheHeader />
<slot />
<LazyTheFooter />
</div>
</template>
```
This is particularly useful if the component is not always needed. By using the `Lazy` prefix you can delay loading the component code until the right moment, which can be helpful for optimizing your JavaScript bundle size.
```html{}[pages/index.vue]
<template>
<div>
<h1>Mountains</h1>
<LazyMountainsList v-if="show" />
<button v-if="!show" @click="show = true">Show List</button>
</div>
</template>
<script>
export default {
data() {
return {
show: false
}
}
}
</script>
```
## Direct Imports
You can also explicitly import components from `#components` if you want or need to bypass Nuxt's auto-importing functionality.
```html{}[pages/index.vue]
<template>
<div>
<h1>Mountains</h1>
<LazyMountainsList v-if="show" />
<button v-if="!show" @click="show = true">Show List</button>
<NuxtLink to="/">Home</NuxtLink>
</div>
</template>
<script setup>
import { NuxtLink, LazyMountainsList } from '#components'
const show = ref(false)
</script>
```
## `<ClientOnly>` Component
Nuxt provides the `<ClientOnly>` component for purposely rendering a component only on client side. To import a component only on the client, register the component in a client-side only plugin.
```html{}[pages/example.vue]
<template>
<div>
<Sidebar />
<ClientOnly>
<!-- this component will only be rendered on client-side -->
<Comments />
</ClientOnly>
</div>
</template>
```
Use a slot as fallback until `<ClientOnly>` is mounted on client side.
```html{}[pages/example.vue]
<template>
<div>
<Sidebar />
<!-- This renders the "span" element on the server side -->
<ClientOnly fallbackTag="span">
<!-- this component will only be rendered on client side -->
<Comments />
<template #fallback>
<!-- this will be rendered on server side -->
<p>Loading comments...</p>
</template>
</ClientOnly>
</div>
</template>
```
<!-- TODO: Add back after passing treeshakeClientOnly experiment -->
<!-- ::alert{type=warning}
Make sure not to _nest_ `<ClientOnly>` components or other client-only components. Nuxt performs an optimization to remove the contents of these components from the server-side render, which can break in this case.
:: -->
## .client Components
If a component is meant to be rendered only client-side, you can add the `.client` suffix to your component.
```bash
| components/
--| Comments.client.vue
```
```html{}[pages/example.vue]
<template>
<div>
<!-- this component will only be rendered on client side -->
<Comments />
</div>
</template>
```
::alert{type=warning}
This feature only works with Nuxt auto-imports and `#components` imports. Explicitly importing these components from their real paths does not convert them into client-only components.
::
::alert{type=warning}
`.client` components are rendered only after being mounted. To access the rendered template using `onMounted()`, add `await nextTick()` in the callback of the `onMounted()` hook.
::
## .server Components
`.server` components can either be used on their own or paired with a `.client` component.
### Standalone server components
Standalone server components will always be rendered on the server. When their props update, this will result in a network request that will update the rendered HTML in-place.
Server components are currently experimental and in order to use them, you need to enable the 'component islands' feature in your nuxt.config:
```ts [nuxt.config.ts]
export default defineNuxtConfig({
experimental: {
componentIslands: true
}
})
```
Now you can register server-only components with the `.server` suffix and use them anywhere in your application automatically.
```bash
| components/
--| HighlightedMarkdown.server.vue
```
```html{}[pages/example.vue]
<template>
<div>
<!--
this will automatically be rendered on the server, meaning your markdown parsing + highlighting
libraries are not included in your client bundle.
-->
<HighlightedMarkdown markdown="# Headline" />
</div>
</template>
```
::alert{type=warning}
Slots are not supported by server components in their current state of development.
::
::alert{type=info}
Please note that there is a known issue with using async code in a server component. It will lead to a hydration mismatch error on initial render. See [#18500](https://github.com/nuxt/nuxt/issues/18500#issuecomment-1403528142). Until there is a workaround, server-components must be synchronous.
::
### Paired with a `.client` component
In this case, the `.server` + `.client` components are two 'halves' of a component and can be used in advanced use cases for separate implementations of a component on server and client side.
```bash
| components/
--| Comments.client.vue
--| Comments.server.vue
```
```html{}[pages/example.vue]
<template>
<div>
<!-- this component will render Comments.server server-side then Comments.client once mounted in client-side -->
<Comments />
</div>
</template>
```
::alert{type=warning}
It is essential that the client half of the component can 'hydrate' the server-rendered HTML. That is, it should render the same HTML on initial load, or you will experience a hydration mismatch.
::
## `<DevOnly>` Component
Nuxt provides the `<DevOnly>` component to render a component only during development.
The content will not be included in production builds and tree-shaken.
```html{}[pages/example.vue]
<template>
<div>
<Sidebar />
<DevOnly>
<!-- this component will only be rendered during development -->
<LazyDebugBar />
</DevOnly>
</div>
</template>
```
## Library Authors
Making Vue component libraries with automatic tree-shaking and component registration is super easy ✨
You can use the `components:dirs` hook to extend the directory list without requiring user configuration in your Nuxt module.
Imagine a directory structure like this:
```bash
| node_modules/
---| awesome-ui/
------| components/
---------| Alert.vue
---------| Button.vue
------| nuxt.js
| pages/
---| index.vue
| nuxt.config.js
```
Then in `awesome-ui/nuxt.js` you can use the `components:dirs` hook:
```js
import { defineNuxtModule } from '@nuxt/kit'
import { fileURLToPath } from 'node:url'
export default defineNuxtModule({
hooks: {
'components:dirs'(dirs) {
// Add ./components dir to the list
dirs.push({
path: fileURLToPath(new URL('./components', import.meta.url)),
prefix: 'awesome'
})
}
}
})
```
That's it! Now in your project, you can import your UI library as a Nuxt module in your `nuxt.config` file:
```js
export default {
modules: ['awesome-ui/nuxt']
}
```
... and directly use the module components (prefixed with `awesome-`) in our `pages/index.vue`:
```vue
<template>
<div>
My <AwesomeButton>UI button</AwesomeButton>!
<awesome-alert>Here's an alert!</awesome-alert>
</div>
</template>
```
It will automatically import the components only if used and also support HMR when updating your components in `node_modules/awesome-ui/components/`.
::LinkExample{link="/docs/examples/auto-imports/components"}
::