JavaScript SEO

Why It Matters

Search engines struggle with JavaScript rendering, potentially missing content or links on JS-heavy sites. Poor JavaScript SEO can result in entire sites being invisible to search engines despite ranking on traditional HTML sites. Proper implementation is mandatory for modern web applications.

How It Works

Search engines must execute JavaScript to see content rendered client-side. Google can render JS but it's resource-intensive and delayed. Solutions include server-side rendering (SSR), static site generation (SSG), dynamic rendering, or hybrid approaches ensuring search engines access fully-rendered HTML.

Use Cases

• A React SPA implements Next.js SSR, allowing Google to index content immediately instead of waiting for JS execution
• An Angular app uses dynamic rendering to serve pre-rendered HTML to bots while maintaining SPA for users
• A Vue.js site adopts static site generation for product pages, ensuring instant indexing

Best Practices

• Implement server-side rendering (SSR) or static site generation (SSG) for critical content
• Test rendering with Google's Mobile-Friendly Test and URL Inspection tool
• Ensure important content isn't hidden in JavaScript that fails to execute
• Use progressive enhancement - ensure core content works without JavaScript
• Implement proper internal linking that search engines can follow before rendering
• Monitor JavaScript errors in Search Console that may prevent indexing