not-found.tsx will appear with two duplicate robots tags

[GreedyWhale]

Link to the code that reproduces this issue

https://github.com/GreedyWhale/nextjs-meta-bug

To Reproduce

1. npx create-next-app@latest

√ What is your project named? ... my-app
√ Would you like to use TypeScript? ... No / Yes
√ Would you like to use ESLint? ... No / Yes
√ Would you like to use Tailwind CSS? ... No / Yes
√ Would you like your code inside a src/ directory? ... No / Yes
√ Would you like to use App Router? (recommended) ... No / Yes
√ Would you like to use Turbopack for next dev? ... No / Yes
√ Would you like to customize the import alias (@/* by default)? ... No / Yes

2. create not-found.tsx file

import type { Metadata } from "next"

export const metadata: Metadata = {
  title: 'My Blog',
  description: '...',
  robots: {
    index: false,
    follow: false
  }
}

export default function NotFound() {
  return (
    <div>
      <div>
        <h2>Not Found</h2>
        <p>Could not find requested resource</p>
      </div>
    </div>
  )
}

3. pnpm run dev
4. Visit http://localhost:3000/xxxx
5. Open your browser's debugging tool to view the html code

Current vs. Expected behavior

Hopefully there is only one <meta=“robots”> tag

Provide environment information

- package.json

{
  "name": "my-app",
  "version": "0.1.0",
  "private": true,
  "scripts": {
    "dev": "next dev --turbopack",
    "build": "next build",
    "start": "next start",
    "lint": "next lint"
  },
  "dependencies": {
    "react": "^19.0.0",
    "react-dom": "^19.0.0",
    "next": "15.1.8"
  },
  "devDependencies": {
    "typescript": "^5",
    "@types/node": "^20",
    "@types/react": "^19",
    "@types/react-dom": "^19",
    "postcss": "^8",
    "tailwindcss": "^3.4.1",
    "eslint": "^9",
    "eslint-config-next": "15.1.8",
    "@eslint/eslintrc": "^3"
  },
  "packageManager": "pnpm@10.5.2+sha256.79a98daa90248b50815e31460790f118c56fe099113370826caa0153be6daba5"
}

Which area(s) are affected? (Select all that apply)

Not sure

Which stage(s) are affected? (Select all that apply)

next dev (local)

Additional context

No response

[KindArt]

NextJS automatically injects the meta tag for 404 pages to prevent them from being indexed.

The notFound function allows you to render the [not-found file](https://nextjs.org/docs/app/api-reference/file-conventions/not-found) within a route segment as well as inject a <meta name="robots" content="noindex" /> tag.

As you've created your own metadata implementation within the not-found.tsx, it's now duplicated.

It won't be duplicated if you remove the robots segment from your metadata implementation:

robots: {
    index: false,
    follow: false
  }

[GreedyWhale]

NextJS会自动为 404 页面注入元标记，以防止它们被编入索引。

The notFound function allows you to render the [not-found file](https://nextjs.org/docs/app/api-reference/file-conventions/not-found) within a route segment as well as inject a <meta name="robots" content="noindex" /> tag.

由于您已经在 中创建了自己的元数据实现not-found.tsx，因此它现在已经重复。

如果您从元数据实施中删除 robots 段，它将不会重复：

robots: {
    index: false,
    follow: false
  }

Thank you, I saw this on the docs but our SEO colleague asked for nofollow and I don't know how to say no, so is this a feature of Next.js and not a bug?

[gaojude]

Right now this behavior is expected and harmless: Next.js automatically injects <meta name="robots" content="noindex"> for any route that returns a 404, including not-found.tsx, while your own robots field (index: false, follow: false) is also being merged in, which results in two tags showing up. From an SEO perspective this is not an actual issue because search engines like Google will simply aggregate the directives across both tags and apply the most restrictive interpretation, so your page is still treated as noindex, nofollow. If you only need the page excluded from search results, you can remove the robots definition from your not-found.tsx and rely on Next.js’ automatic noindex handling, which avoids duplication entirely. If you also want to prevent link equity from flowing through that page, it’s cleaner to mark untrusted links with rel="nofollow" rather than relying on a page-level nofollow, but even if you leave your current setting in place the duplicate tags don’t hurt—this is more of a cosmetic quirk than a functional problem.

Ref: https://developers.google.com/search/blog/2007/03/using-robots-meta-tag

[github-actions]

This closed issue has been automatically locked because it had no new activity for 2 weeks. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.