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---
title: forbidden
description: API Reference for the forbidden function.
version: experimental
related:
links:
- app/api-reference/file-conventions/forbidden
- app/api-reference/functions/not-found
- app/api-reference/functions/unauthorized
- app/api-reference/config/next-config-js/authInterrupts
---
The `forbidden` function throws an error that renders a Next.js 403 page. It's useful for handling authorization errors in your application. You can customize the UI using the [`forbidden.js` file](/docs/app/api-reference/file-conventions/forbidden).
Invoking `forbidden()` throws a `NEXT_HTTP_ERROR_FALLBACK;403` error and terminates rendering of the route segment where it was thrown. Next.js also injects a `<meta name="robots" content="noindex" />` tag so the page is not indexed. Because it works by throwing, call it in the render path: a component, or a function a component `await`s. A call left in an un-awaited promise throws where nothing catches it, and no forbidden UI renders.
To start using `forbidden`, enable the experimental [`authInterrupts`](/docs/app/api-reference/config/next-config-js/authInterrupts) configuration option in your `next.config.js` file:
```ts filename="next.config.ts" switcher
import type { NextConfig } from 'next'
const nextConfig: NextConfig = {
experimental: {
authInterrupts: true,
},
}
export default nextConfig
```
```js filename="next.config.js" switcher
module.exports = {
experimental: {
authInterrupts: true,
},
}
```
`forbidden` can be invoked in [Server Components](/docs/app/getting-started/server-and-client-components), [Server Functions](/docs/app/getting-started/mutating-data), and [Route Handlers](/docs/app/api-reference/file-conventions/route).
```tsx filename="app/admin/page.tsx" switcher
import { verifySession } from '@/app/lib/dal'
import { forbidden } from 'next/navigation'
export default async function AdminPage() {
const session = await verifySession()
// Check if the user has the 'admin' role
if (session.role !== 'admin') {
forbidden()
}
// Render the admin page for authorized users
return <></>
}
```
```jsx filename="app/admin/page.js" switcher
import { verifySession } from '@/app/lib/dal'
import { forbidden } from 'next/navigation'
export default async function AdminPage() {
const session = await verifySession()
// Check if the user has the 'admin' role
if (session.role !== 'admin') {
forbidden()
}
// Render the admin page for authorized users
return <></>
}
```
## Good to know
- The `forbidden` function cannot be called in the [root layout](/docs/app/api-reference/file-conventions/layout#root-layout).
- You do not need to write `return forbidden()`. It throws (its TypeScript [`never`](https://www.typescriptlang.org/docs/handbook/2/functions.html#never) return type), so execution stops. A `try/catch` around the call suppresses the interrupt and no forbidden UI renders. Use [`unstable_rethrow`](/docs/app/api-reference/functions/unstable_rethrow) to let it through.
- A `forbidden()` left in an un-awaited promise throws where nothing catches it, so no forbidden UI renders. In development the server logs `тип unhandledRejection: NEXT_HTTP_ERROR_FALLBACK;403`. Always `await` the function that may call it.
## Examples
### Calling `forbidden()` after streaming has started
To keep the page's shell and loading UI visible while the session is checked, put the role check in the [Data Access Layer](/docs/app/guides/authentication#creating-a-data-access-layer-dal) function that loads the data, and render it in a component wrapped in [`<Suspense>`](https://react.dev/reference/react/Suspense). The check runs inside the boundary, so the shell streams while the session resolves:
```tsx filename="app/projects/page.tsx" switcher highlight={8}
import { Suspense } from 'react'
import { verifySession } from '@/app/lib/dal'
import { forbidden } from 'next/navigation'
async function getProjects() {
const session = await verifySession()
if (session?.role !== 'admin') {
forbidden()
}
return db.projects.findMany()
}
async function Projects() {
const projects = await getProjects()
return (
<ul>
{projects.map((project) => (
<li key={project.id}>{project.name}</li>
))}
</ul>
)
}
export default function ProjectsPage() {
return (
<main>
<h1>Projects</h1>
<Suspense fallback={<p>Loading...</p>}>
<Projects />
</Suspense>
</main>
)
}
```
```jsx filename="app/projects/page.js" switcher highlight={8}
import { Suspense } from 'react'
import { verifySession } from '@/app/lib/dal'
import { forbidden } from 'next/navigation'
async function getProjects() {
const session = await verifySession()
if (session?.role !== 'admin') {
forbidden()
}
return db.projects.findMany()
}
async function Projects() {
const projects = await getProjects()
return (
<ul>
{projects.map((project) => (
<li key={project.id}>{project.name}</li>
))}
</ul>
)
}
export default function ProjectsPage() {
return (
<main>
<h1>Projects</h1>
<Suspense fallback={<p>Loading...</p>}>
<Projects />
</Suspense>
</main>
)
}
```
When the session lacks access, `getProjects` calls `forbidden()`, which throws. Because this happens during rendering, the exception propagates to the nearest [`forbidden`](/docs/app/api-reference/file-conventions/forbidden) boundary, which renders in place of the streamed-in content, even though the page shell has already been sent.
Add a `forbidden.tsx` alongside the route to define that UI:
```tsx filename="app/projects/forbidden.tsx" switcher
export default function Forbidden() {
return (
<main>
<h1>403 - Forbidden</h1>
<p>You don't have access to this page.</p>
</main>
)
}
```
```jsx filename="app/projects/forbidden.js" switcher
export default function Forbidden() {
return (
<main>
<h1>403 - Forbidden</h1>
<p>You don't have access to this page.</p>
</main>
)
}
```
The trade-off is the HTTP status code. Because the check runs inside the `<Suspense>` boundary, the response has already begun streaming as a `200`, and the status can't change once streaming has started. This is usually fine for a page, where the user sees the `forbidden` UI regardless. To return a real `403` status, the check has to run before the response streams. With [Cache Components](/docs/app/getting-started/caching), every dynamic route streams a static shell first, so run that check in [`proxy`](/docs/app/api-reference/file-conventions/proxy) instead. See [Status codes](/docs/app/api-reference/file-conventions/loading#status-codes).
### Role-based route protection
You can use `forbidden` to restrict access to certain routes based on user roles. This ensures that users who are authenticated but lack the required permissions cannot access the route.
```tsx filename="app/admin/page.tsx" switcher
import { verifySession } from '@/app/lib/dal'
import { forbidden } from 'next/navigation'
export default async function AdminPage() {
const session = await verifySession()
// Check if the user has the 'admin' role
if (session.role !== 'admin') {
forbidden()
}
// Render the admin page for authorized users
return (
<main>
<h1>Admin Dashboard</h1>
<p>Welcome, {session.user.name}!</p>
</main>
)
}
```
```jsx filename="app/admin/page.js" switcher
import { verifySession } from '@/app/lib/dal'
import { forbidden } from 'next/navigation'
export default async function AdminPage() {
const session = await verifySession()
// Check if the user has the 'admin' role
if (session.role !== 'admin') {
forbidden()
}
// Render the admin page for authorized users
return (
<main>
<h1>Admin Dashboard</h1>
<p>Welcome, {session.user.name}!</p>
</main>
)
}
```
### Mutations with Server Actions
When implementing mutations in Server Actions, you can use `forbidden` to only allow users with a specific role to update sensitive data.
```ts filename="app/actions/update-role.ts" switcher
'use server'
import { verifySession } from '@/app/lib/dal'
import { forbidden } from 'next/navigation'
import db from '@/app/lib/db'
export async function updateRole(formData: FormData) {
const session = await verifySession()
// Ensure only admins can update roles
if (session.role !== 'admin') {
forbidden()
}
// Perform the role update for authorized users
// ...
}
```
```js filename="app/actions/update-role.js" switcher
'use server'
import { verifySession } from '@/app/lib/dal'
import { forbidden } from 'next/navigation'
import db from '@/app/lib/db'
export async function updateRole(formData) {
const session = await verifySession()
// Ensure only admins can update roles
if (session.role !== 'admin') {
forbidden()
}
// Perform the role update for authorized users
// ...
}
```
## Version History
| Version | Changes |
| --------- | ----------------------- |
| `v15.1.0` | `forbidden` introduced. |