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title: Custom Errors
description: Override and extend the built-in Error page to handle custom errors.
---
## 404 Page
A 404 page may be accessed very often. Server-rendering an error page for every visit increases the load of the Next.js server. This can result in increased costs and slow experiences.
To avoid the above pitfalls, Next.js provides a static 404 page by default without having to add any additional files.
### Customizing The 404 Page
To create a custom 404 page you can create a `pages/404.js` file. This file is statically generated at build time.
```jsx filename="pages/404.js"
export default function Custom404() {
return <h1>404 - Page Not Found</h1>
}
```
> **Good to know**: You can use [`getStaticProps`](/docs/pages/building-your-application/data-fetching/get-static-props) inside this page if you need to fetch data at build time.
## 500 Page
Server-rendering an error page for every visit adds complexity to responding to errors. To help users get responses to errors as fast as possible, Next.js provides a static 500 page by default without having to add any additional files.
### Customizing The 500 Page
To customize the 500 page you can create a `pages/500.js` file. This file is statically generated at build time.
```jsx filename="pages/500.js"
export default function Custom500() {
return <h1>500 - Server-side error occurred</h1>
}
```
> **Good to know**: You can use [`getStaticProps`](/docs/pages/building-your-application/data-fetching/get-static-props) inside this page if you need to fetch data at build time.
### More Advanced Error Page Customizing
500 errors are handled both client-side and server-side by the `Error` component. If you wish to override it, define the file `pages/_error.js` and add the following code:
```jsx
function Error({ statusCode }) {
return (
<p>
{statusCode
? `An error ${statusCode} occurred on server`
: 'An error occurred on client'}
</p>
)
}
Error.getInitialProps = ({ res, err }) => {
const statusCode = res ? res.statusCode : err ? err.statusCode : 404
return { statusCode }
}
export default Error
```
> `pages/_error.js` is only used in production. In development you’ll get an error with the call stack to know where the error originated from.
### Reusing the built-in error page
If you want to render the built-in error page you can by importing the `Error` component:
```jsx
import Error from 'next/error'
export async function getServerSideProps() {
const res = await fetch('https://api.github.com/repos/vercel/next.js')
const errorCode = res.ok ? false : res.status
const json = await res.json()
return {
props: { errorCode, stars: json.stargazers_count },
}
}
export default function Page({ errorCode, stars }) {
if (errorCode) {
return <Error statusCode={errorCode} />
}
return <div>Next stars: {stars}</div>
}
```
The `Error` component also takes `title` as a property if you want to pass in a text message along with a `statusCode`.
If you have a custom `Error` component be sure to import that one instead. `next/error` exports the default component used by Next.js.
### Caveats
- `Error` does not currently support Next.js [Data Fetching methods](/docs/pages/building-your-application/data-fetching) like [`getStaticProps`](/docs/pages/building-your-application/data-fetching/get-static-props) or [`getServerSideProps`](/docs/pages/building-your-application/data-fetching/get-server-side-props).
- `_error`, like `_app`, is a reserved pathname. `_error` is used to define the customized layouts and behaviors of the error pages. `/_error` will render 404 when accessed directly via [routing](/docs/pages/building-your-application/routing) or rendering in a [custom server](/docs/pages/guides/custom-server).
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