Mobile-First Indexing
Google predominantly uses the mobile version of your site for indexing and ranking. If your mobile experience is broken or missing content, that's what Google sees.
Why It Matters
Since 2023, Google's entire index is mobile-first. This means Google evaluates your site based on its mobile version, not desktop. If your mobile site has less content, different structure, or technical issues, that's what determines your rankings - even for desktop searches.
This was a major shift that caught many sites off guard. Sites that had stripped-down mobile versions, content hidden behind "read more" toggles, or separate mobile URLs (m.example.com) suddenly found their rankings based on an inferior version of their content.
In Practice
Use responsive design - one URL, one set of content that adapts to screen size. This is the simplest way to ensure mobile and desktop content are identical.
Check that all content visible on desktop is also accessible on mobile. Expandable sections, tabs, and accordions are fine - Google can see that content. But content completely removed from the mobile version is content Google ignores.
Test your mobile experience in Google Search Console's Mobile Usability report and with the URL Inspection tool (set to mobile). Fix any mobile-specific issues: text too small, clickable elements too close together, content wider than screen.
Related Terms
Glossary
Core Web Vitals
Google's page experience metrics - loading speed, visual stability, and interactivity.
Glossary
Googlebot
Google's web crawler that discovers, downloads, and indexes your pages.
Glossary
User Experience (UX)
How easy and enjoyable your site is to use - bad UX directly hurts rankings.
Glossary
Technical SEO
Optimising your site's infrastructure so search engines can crawl, render, and index it.
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