Technical SEO
Mobile-First Indexing
Google's approach of primarily using the mobile version of a page for indexing and ranking.
CurrentLast updated: 2026-09-16
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Definition
Technical SEOMobile-first indexing means Google predominantly uses the mobile version of a page's content for indexing and ranking. Since 2019, Google has used mobile-first indexing for all new sites, and by 2021 it applied to all sites. Sites without mobile-compatible content may suffer in rankings.
Why it matters
With mobile-first indexing, the mobile version of your site is the primary version Google evaluates.
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