What is Mobile-First Indexing? #
Google primarily uses the mobile version of your site (crawled by smartphone user-agent) to index and rank your pages. So, your mobile site’s content matters most.
1. Create a Mobile-Friendly Site #
Choose one of these configurations:
- Responsive Design (Recommended):
Same URL and HTML for all devices, content adapts via CSS. Easiest to maintain. - Dynamic Serving:
Same URL, but different HTML served based on device. Use Vary: User-Agent header. - Separate URLs (e.g., m.example.com):
Different URLs and HTML for desktop and mobile. Use Vary: User-Agent header and proper canonical/alternate tags.
2. Make Content Accessible to Google #
- Use the same robots meta tags (e.g., noindex, nofollow) on desktop & mobile.
- Avoid lazy-loading primary content behind user interactions (click/swipe).
- Don’t block mobile resources (CSS, JS, images) in robots.txt.
- Ensure content parity: mobile should have the same main content as desktop.
- You can use accordions or tabs on mobile to save space, but content must be equivalent.
- You can use accordions or tabs on mobile to save space, but content must be equivalent.
- Use same headings on mobile and desktop.
3. Structured Data & Metadata #
- Add structured data on both desktop and mobile.
- URLs in structured data should match the respective version (mobile URLs on mobile site).
- Ensure title tags and meta descriptions are equivalent across versions.
4. Ads & Visual Content #
- Avoid intrusive ads that harm mobile UX or rankings.
- Use high-quality images on mobile, with descriptive alt text (same as desktop).
- Avoid image URLs that change with every page load.
- Use supported image and video formats.
- Place videos where mobile users can easily find them.
5. Extra Tips for Separate URL Setup (m-dot sites) #
- Error pages should match across desktop and mobile.
- Avoid URL fragments (#something) on mobile URLs.
- Ensure redirects don’t cause multiple URLs to point to a single page without equivalent content.
- Verify both desktop and mobile sites in Google Search Console.
- For international sites, link hreflang tags correctly:
- Mobile URLs link hreflang → mobile URLs
- Desktop URLs link hreflang → desktop URLs
- Mobile URLs link hreflang → mobile URLs
- Mobile URLs should have rel=canonical pointing to desktop URLs.
- Desktop URLs should have rel=alternate pointing to mobile URLs.
Example mobile canonical tag:
<link rel=”canonical” href=”https://example.com/”>
Example hreflang for mobile URLs:
<link rel=”alternate” hreflang=”es” href=”https://m.example.com/es/”>
6. Crawl Budget & Robots.txt #
- Ensure your mobile site can handle increased crawl rate.
- Use consistent robots.txt rules on both versions.
Summary #
- Responsive design is easiest and recommended.
- Mobile content should be as rich and complete as desktop content.
- Use proper canonical and alternate tags if using separate URLs.
- Keep structured data and metadata consistent.
- Avoid blocking essential content and resources from Googlebot.
- Test mobile usability regularly and verify in Search Console.
Mobile-First Indexing Troubleshooting Guide #
1. Missing Structured Data #
Cause: Mobile page lacks the structured data present on desktop.
Fix:
- Ensure identical structured data on both mobile & desktop.
- Use correct, updated URLs in structured data.
- Check for extraction errors in Data Highlighter or Search Console.
- Use URL Inspection tool to confirm content visibility.
2. Noindex Tag on Mobile Pages #
Cause: Mobile pages blocked by noindex meta tag.
Fix:
- Use same robots meta tags on mobile & desktop.
- Remove noindex from mobile pages to allow indexing.
3. Missing or Blocked Images #
Cause: Important images missing or blocked by robots.txt on mobile.
Fix:
- Ensure mobile site contains all critical images like desktop.
- Don’t block images in robots.txt.
- Use supported image formats and tags.
- Avoid lazy-loading primary images behind user interactions.
4. Low Quality or Missing Alt Text for Images #
Cause: Images are too small, low resolution, or missing alt text on mobile.
Fix:
- Use high-resolution, properly sized images on mobile.
- Provide descriptive alt text matching desktop versions.
5. Missing Page Title or Meta Description #
Cause: Mobile pages lack title or meta description.
Fix:
- Ensure mobile and desktop titles and meta descriptions are equivalent.
6. Mobile URL Is an Error Page #
Cause: Mobile page returns error while desktop serves content.
Fix:
- Make error status consistent across desktop and mobile.
7. Mobile URL Has Anchor Fragment (#) #
Cause: Mobile URLs include fragments which Google can’t index.
Fix:
- Remove URL fragments from mobile URLs.
8. Mobile Page Blocked by Robots.txt #
Cause: Mobile pages blocked by robots.txt disallow rules.
Fix:
- Use consistent robots.txt rules on desktop and mobile.
- Allow Googlebot to crawl essential mobile resources.
9. Duplicate Mobile Page Target #
Cause: Multiple desktop URLs redirect to the same mobile URL.
Fix:
- Ensure every desktop page with unique content has an equivalent mobile page.
- Avoid redirecting multiple desktop pages to a single mobile page.
10. Desktop Redirects to Mobile Home Page #
Cause: Desktop pages redirect broadly to mobile homepage.
Fix:
- Ensure desktop pages redirect to their exact mobile equivalents.
11. Page Quality Issues on Mobile #
Cause: Ads, missing content, or poor titles on mobile.
Fix:
- Follow Better Ads Standards for mobile ads.
- Maintain content parity (titles, headings, images, text) between desktop and mobile.
12. Video Issues #
Cause: Videos on mobile unsupported, hard to find, or slow loading.
Fix:
- Use supported video formats & HTML tags (<video>, <embed>, <object>).
- Don’t lazy-load videos behind interactions.
- Place videos prominently on mobile pages for easy access.
13. Hostload Issues #
Cause: Server can’t handle increased mobile crawl rate.
Fix:
- Ensure your hosting can handle potential increase in Googlebot mobile crawling.