AI Search Visibility Fragments Across Platforms, Study Finds

Brand visibility varies wildly across AI search platforms

A brand's prominence in one AI search engine offers little indication of its standing in another, according to new research that challenges assumptions about unified AI visibility strategies.

Semrush's 2026 AI Visibility Index analyzed 126 million U.S. AI search prompts collected between January and April 2026, tracking how ChatGPT, Google Gemini, Google AI Mode, and Google AI Overviews reference and cite more than 1,200 brands across 22 industries. The study, first reported by Forbes, found only 36 brands appeared in the top 100 most-mentioned list across all four platforms throughout the study period. Those 36 were household names including Google, Amazon, Facebook, Apple, Walmart, Disney, and Nintendo.

The remaining brands exhibited gaps in visibility across different platforms, revealing a fragmented landscape where success on one AI system does not guarantee presence on others.

Why it matters

As enterprises allocate budgets for AI visibility initiatives, single-platform audits systematically overstate actual brand findability. The fragmentation means potential customers may encounter a brand through one AI interface while finding competitors dominate another. With Semrush reporting that visitors from AI search convert at 4.4 times the rate of traditional organic search visitors, these visibility gaps represent missed opportunities at the exact moment informed buyers make purchase decisions.

Different citation models drive inconsistency

The fragmentation stems from fundamental differences in how platforms construct responses. ChatGPT cites an average of 15 sources per response, while Gemini uses just three, according to the Index. This structural difference means a brand comfortably included in ChatGPT's broader source pool can fall outside Gemini's narrower selection when answering identical queries.

The platforms show greater overlap in certain source types. Community and Q&A platforms, encyclopedic references, and discussion threads appear frequently across multiple AI systems. These sources carry structural advantages: continuous updates, question-based formatting that mirrors natural queries, and comparative language that AI systems need to formulate recommendations.

Quora emerged as a particularly consistent source, appearing in over 7 percent of Google AI Mode responses and ranking as the top-cited domain in Google AI Overviews. In Semrush's analysis of 278,000 prompts and 26,000 cited Quora URLs, questions earning citations averaged 37 replies and 15 upvotes, suggesting conversation depth influences citation selection.

Audit recommendations

The research points to specific steps for brands seeking consistent AI visibility. Organizations should test their highest-intent category questions separately across ChatGPT, Gemini, AI Mode, and AI Overviews, recording which brands and sources appear in each system rather than relying on aggregated metrics.

Examining the domains cited alongside a brand's category reveals where AI visibility gets built. For most B2B categories, this includes community platforms no single brand controls. Consistent presence requires ongoing participation—subject-matter experts answering questions over time rather than one-time content initiatives.

The findings were published in Semrush's 2026 AI Visibility Index in June 2026.