Your Next.js middleware redirects to /login, but /login also triggers the middleware, which redirects to /login again. Infinite loop. The browser shows “ERR_TOO_MANY_REDIRECTS.”

What causes this error

1. Middleware runs on the redirect target — your matcher catches /login too
2. Missing pathname check — you redirect all unauthenticated requests without excluding public pages
3. Cookie not being set — the auth cookie isn’t persisted, so every request looks unauthenticated

Fix 1: Exclude public routes from the matcher

// middleware.ts
export const config = {
  matcher: [
    // Match all paths EXCEPT static files, api routes, and public pages
    '/((?!api|_next/static|_next/image|favicon.ico|login|signup|public).*)',
  ],
};

Fix 2: Check the pathname inside middleware

import { NextResponse } from 'next/server';
import type { NextRequest } from 'next/server';

const publicPaths = ['/login', '/signup', '/forgot-password', '/'];

export function middleware(request: NextRequest) {
  const { pathname } = request.nextUrl;
  
  // Don't redirect if already on a public page
  if (publicPaths.some(path => pathname.startsWith(path))) {
    return NextResponse.next();
  }

  const token = request.cookies.get('auth-token');
  if (!token) {
    return NextResponse.redirect(new URL('/login', request.url));
  }

  return NextResponse.next();
}

Fix 3: Check for redirect loops explicitly

// Prevent redirect loops by checking the referer
const referer = request.headers.get('referer');
if (referer?.includes('/login')) {
  return NextResponse.next(); // Don't redirect again
}

How to debug

Add logging to your middleware to see what’s happening:

export function middleware(request: NextRequest) {
  console.log('Middleware:', request.nextUrl.pathname);
  // ... rest of middleware
}

Check the terminal (not browser console) — middleware runs on the server.

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