Build a sitemap and robots file in Next.js

Next.js gives you sitemaps and a robots file as first-class conventions, so you do not need a plugin or a hand-maintained XML file. Two small files in the app directory keep both in sync with your real routes. Here is how.

The sitemap

Create app/sitemap.ts that default-exports a function returning your URLs.

import type { MetadataRoute } from "next";

export default function sitemap(): MetadataRoute.Sitemap {
  const base = "https://example.com";
  return [
    { url: `${base}/`, lastModified: new Date("2026-01-01"), priority: 1 },
    { url: `${base}/about`, lastModified: new Date("2026-01-01") },
  ];
}

Next serves this at /sitemap.xml and handles the XML for you.

Include dynamic pages

The real power is generating entries from your content. Read your posts and map them:

const posts = getAllPosts().map((p) => ({
  url: `${base}/blog/${p.slug}`,
  lastModified: new Date(p.updated),
}));

Because the file runs at build time, the sitemap regenerates from your actual posts on every build. Add a post, rebuild, and it appears with no manual step.

The robots file

Create app/robots.ts alongside it.

import type { MetadataRoute } from "next";

export default function robots(): MetadataRoute.Robots {
  return {
    rules: [{ userAgent: "*", allow: "/", disallow: ["/admin/"] }],
    sitemap: "https://example.com/sitemap.xml",
  };
}

Point it at your sitemap so crawlers discover it, and never block the paths that hold your CSS and JS, because crawlers need them to render the page.

Two details worth getting right

• Real lastmod dates. Use each page's actual last-modified date, not the build time. A lastmod that changes every deploy tells search engines nothing and may be ignored.
• Only canonical, indexable URLs. Leave out redirects, error pages, and anything you mark noindex, so the sitemap is a clean list of pages you want found.

That is the whole setup: two files, generated from your content, always in step with the site. For more on the markup side, see how to add JSON-LD.