Mobile-First Indexing: Requirements and Best Practices
Google now uses the mobile version of your site for indexing and ranking. If your mobile experience is inferior to desktop, your rankings will suffer regardless of how good the desktop version is.
Key Takeaways
- Since 2021, Google predominantly uses the mobile version of content for indexing and ranking.
- The mobile version must contain the same content as desktop: text, images, videos, links, and structured data.
- Use Google's Mobile-Friendly Test tool
- ## Requirements ### Content Parity The mobile version must contain the same content as desktop: text, images, videos, links, and structured data.
What Is Mobile-First Indexing
Since 2021, Google predominantly uses the mobile version of content for indexing and ranking. This means the Googlebot crawler fetches your pages as a mobile user agent. Content that only appears on desktop is effectively invisible to Google.
Requirements
Content Parity
The mobile version must contain the same content as desktop: text, images, videos, links, and structured data. Hidden-by-default content (behind accordions or tabs) is fine as long as it is in the DOM and accessible.
Responsive Design
Google recommends responsive design over separate mobile URLs (m.example.com) or dynamic serving. Responsive design uses a single URL and HTML that adapts via CSS media queries.
Viewport Meta Tag
Without this tag, mobile browsers render the page at desktop width and scale it down, making text unreadable and interactive elements too small.
Technical Checklist
| Check | Why It Matters |
|---|---|
| Same structured data on mobile and desktop | JSON-LD must be present in mobile HTML |
| Same meta tags (title, description, robots) | Mobile version drives indexing |
| Images with alt text on mobile | Image SEO depends on mobile version |
| Touch targets ≥ 48×48px | Google's mobile usability test |
| No horizontal scrolling | Mobile UX signal |
| Text readable without zooming | Font size ≥ 16px for body |
Testing
- Use Google's Mobile-Friendly Test tool
- Check Search Console for mobile usability errors
- Test on real devices (not just DevTools emulation)
- Verify that lazy-loaded content is visible to Googlebot by checking the cached version in Search Console's URL Inspection tool