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.
To create a custom 404 page you can create a pages/404.js
file. This file is statically generated at build time.
// pages/404.js
export default function Custom404() {
return <h1>404 - Page Not Found</h1>
}
Note: You can use
getStaticProps
inside this page if you need to fetch data at build time.
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.
To customize the 500 page you can create a pages/500.js
file. This file is statically generated at build time.
// pages/500.js
export default function Custom500() {
return <h1>500 - Server-side error occurred</h1>
}
Note: You can use
getStaticProps
inside this page if you need to fetch data at build time.
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:
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.
If you want to render the built-in error page you can by importing the Error
component:
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.statusCode
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.