The Next.js SEO Checklist: Metadata, Sitemaps, Schema and Speed

Next.js gives you excellent SEO building blocks out of the box, but they only work if you wire them up deliberately. This is the checklist I follow when shipping production sites with the App Router — including this one.

#1. Use the Metadata API everywhere

Every route should export metadata or generateMetadata. Define a title template once in the root layout and give each page a unique title and description.

export const metadata = {
  title: { default: "Jane Doe — Web Developer", template: "%s | Jane Doe" },
  description: "SEO-ready websites built with Next.js.",
  metadataBase: new URL("https://example.com"),
};

Setting metadataBase lets you use relative URLs for canonical and Open Graph images.

#2. Canonical URLs and hreflang

Duplicate URLs split ranking signals. Set alternates.canonical on every page. For multilingual sites, add alternates.languages so each locale points to the others — and include an x-default.

alternates: {
  canonical: "/en/blog/my-post",
  languages: { tr: "/tr/blog/yazim", en: "/en/blog/my-post", "x-default": "/tr/blog/yazim" },
}

#3. A dynamic sitemap and robots.txt

Use app/sitemap.ts and app/robots.ts. When content lives in a database, generate the sitemap from it so new posts appear automatically, with accurate lastModified dates.

#4. Structured data (JSON-LD)

Add JSON-LD with a <script type="application/ld+json"> tag inside your page component:

• Person or Organization on the home page
• WebSite for the site entity
• BlogPosting for articles (headline, dates, author, image)
• BreadcrumbList for nested pages

Validate with Google's Rich Results Test.

#5. Render content on the server

Server Components send real HTML on the first response, which crawlers can read immediately. Keep client components for interactivity only — this also reduces JavaScript and helps INP.

#6. Open Graph and social previews

Provide openGraph and twitter metadata with a 1200×630 image. Articles should use type: "article" with publishedTime and modifiedTime.

#7. Core Web Vitals

• Use next/font to self-host fonts and avoid layout shift.
• Give every image explicit dimensions; prioritize the LCP image.
• Avoid heavy third-party scripts or load them with next/script and a lazy strategy.
• Aim for LCP ≤ 2.5 s, INP ≤ 200 ms and CLS ≤ 0.1 at the 75th percentile.

#8. Clean, stable URLs

Keep slugs short and lowercase. When you restructure, add permanent (301/308) redirects from old URLs — never let years of accumulated links fall into 404s.

#9. Deploy close to your users

Edge platforms such as Cloudflare Workers serve pages from data centers near each visitor, which noticeably reduces server response time worldwide.

#10. Measure

Verify the site in Google Search Console, submit the sitemap and watch the Page Indexing and Core Web Vitals reports after every major release.

#Wrapping up

SEO in Next.js is less about tricks and more about consistent fundamentals: unique metadata, clean URLs, server-rendered content, structured data and speed. If you'd like help auditing or building an SEO-ready Next.js site, get in touch.