Glossary · Technical
Mobile-first indexing
Definition. Mobile-first indexing means Google uses the mobile version of your page for indexing and ranking. Anything present on desktop but missing on mobile is effectively invisible to Google.
The classic failure is content hidden behind mobile-only accordions or omitted from the mobile template to save space. If it is not in the mobile HTML, it is not being indexed.
Structured data and metadata must match across versions too, not just the visible copy.
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More in Technical: Internal linking · Anchor text · Orphan page · Crawl budget · Indexation · Canonical URL · Duplicate content · Keyword cannibalization
Frequently asked questions
What does Mobile-first indexing mean?
Mobile-first indexing means Google uses the mobile version of your page for indexing and ranking. Anything present on desktop but missing on mobile is effectively invisible to Google.
Why does Mobile-first indexing matter for AI SEO?
The classic failure is content hidden behind mobile-only accordions or omitted from the mobile template to save space. If it is not in the mobile HTML, it is not being indexed.
What is the most common mistake with mobile-first indexing?
Structured data and metadata must match across versions too, not just the visible copy.
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