rsnext/docs/api-reference/next/head.md
Luis Alvarez D d1fdd2bbf8 Add descriptions to documentation pages (#9901)
* Added descriptions

* Added descriptions to API Reference

* Added descriptions to API Routes

* Added descriptions to basic features

* Added descriptions to the routing docs

* Update exportPathMap.md

Co-authored-by: Joe Haddad <timer150@gmail.com>
2020-01-03 13:16:51 -05:00

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---
description: Add custom elements to the `head` of your page with the built-in Head component.
---
# next/head
<details>
<summary><b>Examples</b></summary>
<ul>
<li><a href="https://github.com/zeit/next.js/tree/canary/examples/head-elements">Head Elements</a></li>
<li><a href="https://github.com/zeit/next.js/tree/canary/examples/layout-component">Layout Component</a></li>
</ul>
</details>
We expose a built-in component for appending elements to the `head` of the page:
```jsx
import Head from 'next/head'
function IndexPage() {
return (
<div>
<Head>
<title>My page title</title>
<meta name="viewport" content="initial-scale=1.0, width=device-width" />
</Head>
<p>Hello world!</p>
</div>
)
}
export default IndexPage
```
To avoid duplicate tags in your `head` you can use the `key` property, which will make sure the tag is only rendered once, as in the following example:
```jsx
import Head from 'next/head'
function IndexPage() {
return (
<div>
<Head>
<title>My page title</title>
<meta
name="viewport"
content="initial-scale=1.0, width=device-width"
key="viewport"
/>
</Head>
<Head>
<meta
name="viewport"
content="initial-scale=1.2, width=device-width"
key="viewport"
/>
</Head>
<p>Hello world!</p>
</div>
)
}
export default IndexPage
```
In this case only the second `<meta name="viewport" />` is rendered.
> The contents of `head` get cleared upon unmounting the component, so make sure each page completely defines what it needs in `head`, without making assumptions about what other pages added.
> `title` and `meta` elements need to be contained as **direct** children of the `Head` element, or wrapped into maximum one level of `<React.Fragment>`, otherwise the meta tags won't be correctly picked up on client-side navigations.