Technical SEO
Mobile-First Indexing
Mobile-first indexing means Google predominantly uses the mobile version of a page for indexing and ranking.
If content or structured data exists on desktop but is missing on mobile, it may not be counted. A responsive site that serves the same content to all devices avoids this problem entirely.
The audit that matters is a content parity check: crawl the site as a mobile user agent and diff what disappears. Accordions and tabs are fine, hidden-for-layout content still counts, but content removed from the mobile DOM entirely does not exist for ranking. Structured data and meta tags drift out of parity most often, because desktop templates get maintained and mobile variants get forgotten. Responsive sites sidestep the whole class of problem, which is much of why they became the default recommendation.
Example
A B2B site shows detailed specification tables on desktop but hides them on mobile to keep the page tidy. Google indexes the mobile version, so those specs effectively do not exist for ranking. Queries that matched the tables slide. Restoring the content on mobile inside collapsible sections, still crawlable, recovers the lost queries the next quarter.
Frequently asked questions
- How do I check what Google sees on mobile?
- Use URL Inspection in Search Console and view the rendered mobile HTML, or crawl the site with a mobile user agent and compare against desktop. Anything present on desktop but absent from the mobile DOM is effectively invisible to ranking.
- Does content hidden in accordions or tabs count on mobile?
- Yes. Content collapsed for layout reasons is still in the DOM and still counts. Content stripped from mobile entirely does not. The distinction is whether the text exists in the mobile page source, not whether it is visible on first look.
Related terms
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