Use when adding authentication to Next.js applications with both server and client-side auth - supports App Router and Pages Router with @auth0/nextjs-auth0 SDK
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Add authentication to Next.js applications using @auth0/nextjs-auth0. Supports both App Router and Pages Router.
auth0-quickstart skill firstauth0-react for Vite/CRA SPAsauth0-react-native for iOS/Androidnpm install @auth0/nextjs-auth0For automated setup with Auth0 CLI, see Setup Guide for complete scripts.
For manual setup:
Create .env.local:
AUTH0_SECRET=<generate-a-32-character-secret>
APP_BASE_URL=http://localhost:3000
AUTH0_DOMAIN=your-tenant.auth0.com
AUTH0_CLIENT_ID=your-client-id
AUTH0_CLIENT_SECRET=your-client-secretGenerate secret: openssl rand -hex 32
Important: Add .env.local to .gitignore
Create lib/auth0.ts:
import { Auth0Client } from '@auth0/nextjs-auth0/server';
export const auth0 = new Auth0Client({
domain: process.env.AUTH0_DOMAIN!,
clientId: process.env.AUTH0_CLIENT_ID!,
clientSecret: process.env.AUTH0_CLIENT_SECRET!,
secret: process.env.AUTH0_SECRET!,
appBaseUrl: process.env.APP_BASE_URL!,
});Middleware Configuration (Next.js 15 vs 16):
Next.js 15 - Create middleware.ts at project root:
import { NextRequest } from 'next/server';
import { auth0 } from './lib/auth0';
export async function middleware(request: NextRequest) {
return await auth0.middleware(request);
}
export const config = {
matcher: [
'/((?!_next/static|_next/image|favicon.ico|sitemap.xml|robots.txt).*)',
],
};Next.js 16 - You have two options:
Option 1: Use middleware.ts (same as Next.js 15):
import { NextRequest } from 'next/server';
import { auth0 } from './lib/auth0';
export async function middleware(request: NextRequest) {
return await auth0.middleware(request);
}
export const config = {
matcher: [
'/((?!_next/static|_next/image|favicon.ico|sitemap.xml|robots.txt).*)',
],
};Option 2: Use proxy.ts at project root:
import { NextRequest } from 'next/server';
import { auth0 } from './lib/auth0';
export async function proxy(request: NextRequest) {
return await auth0.middleware(request);
}
export const config = {
matcher: [
'/((?!_next/static|_next/image|favicon.ico|sitemap.xml|robots.txt).*)',
],
};This automatically creates endpoints:
/auth/login - Login/auth/logout - Logout/auth/callback - OAuth callback/auth/profile - User profileNote: In v4, wrapping with <Auth0Provider> is optional. Only needed if you want to pass an initial user during server rendering to useUser().
App Router - Optionally wrap app in app/layout.tsx:
import { Auth0Provider } from '@auth0/nextjs-auth0/client';
import { auth0 } from './lib/auth0';
export default async function RootLayout({ children }: { children: React.ReactNode }) {
const session = await auth0.getSession();
return (
<html>
<body>
<Auth0Provider user={session?.user}>{children}</Auth0Provider>
</body>
</html>
);
}Pages Router - Optionally wrap app in pages/_app.tsx:
import { Auth0Provider } from '@auth0/nextjs-auth0/client';
import type { AppProps } from 'next/app';
export default function App({ Component, pageProps }: AppProps) {
return (
<Auth0Provider user={pageProps.user}>
<Component {...pageProps} />
</Auth0Provider>
);
}Client Component (works in both routers):
'use client'; // Only needed for App Router
import { useUser } from '@auth0/nextjs-auth0/client';
export default function Profile() {
const { user, isLoading } = useUser();
if (isLoading) return <div>Loading...</div>;
if (user) {
return (
<div>
<img src={user.picture} alt={user.name} />
<h2>Welcome, {user.name}!</h2>
<a href="/auth/logout">Logout</a>
</div>
);
}
return <a href="/auth/login">Login</a>;
}Start your dev server:
npm run devVisit http://localhost:3000 and test the login flow.
| Mistake | Fix |
|---|---|
| Using v3 environment variables | v4 uses APP_BASE_URL and AUTH0_DOMAIN (not AUTH0_BASE_URL or AUTH0_ISSUER_BASE_URL) |
| Forgot to add callback URL in Auth0 Dashboard | Add /auth/callback to Allowed Callback URLs (e.g., http://localhost:3000/auth/callback) |
| Missing middleware configuration | v4 requires middleware to mount auth routes - create middleware.ts (Next.js 15+16) or proxy.ts (Next.js 16 only) with auth0.middleware() |
| Wrong route paths | v4 uses /auth/login not /api/auth/login - routes drop the /api prefix |
| Missing or weak AUTH0_SECRET | Generate secure secret with openssl rand -hex 32 and store in .env.local |
| Using .env instead of .env.local | Next.js requires .env.local for local secrets, and .env.local should be in .gitignore |
| App created as SPA type in Auth0 | Must be Regular Web Application type for Next.js |
| Using removed v3 helpers | v4 removed withPageAuthRequired and withApiAuthRequired - use getSession() instead |
| Using useUser in Server Component | useUser is client-only, use auth0.getSession() for Server Components |
| AUTH0_DOMAIN includes https:// | v4 AUTH0_DOMAIN should be just the domain (e.g., example.auth0.com), no scheme |
auth0-quickstart - Basic Auth0 setupauth0-migration - Migrate from another auth providerauth0-mfa - Add Multi-Factor AuthenticationV4 Setup:
lib/auth0.ts with Auth0Client instancemiddleware.ts with middleware() functionmiddleware.ts with middleware() OR proxy.ts with proxy() function<Auth0Provider> for SSR userClient-Side Hooks:
useUser() - Get user in client componentsuser - User profile objectisLoading - Loading stateServer-Side Methods:
auth0.getSession() - Get session in Server Components/API routes/middlewareauth0.getAccessToken() - Get access token for calling APIsCommon Use Cases:
/auth/login and /auth/logout paths (see Step 5)8a541a4
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