AI Search

Semrush's AI Visibility Index Shows Search Fragmenting Fast

Semrush's expanded AI Visibility Index found only 36 brands stay visible across ChatGPT, Gemini, and Google's AI search tools at the same time.

AI Search

Semrush's AI Visibility Index Shows Search Fragmenting Fast

The short version

THE SHORT VERSION: Semrush's expanded 2026 AI Visibility Index analyzed 126 million U.S. AI search prompts and found only 36 brands hold visibility across ChatGPT, Gemini, Google AI Mode, and Google AI Overviews all at once, while 45% of marketing leaders say they can't accurately measure their own AI visibility.

What happened

Semrush released an expanded version of its 2026 AI Visibility Index, scaling its analysis from an initial 2,500-prompt sample to 126 million U.S. AI search prompts collected between January and April 2026 across ChatGPT, Gemini, Google AI Mode, and Google AI Overviews. The index found that only 36 brands maintained top-100 visibility across all four platforms at once, out of the thousands tracked across 22 industries. Citation behavior diverges sharply by platform: ChatGPT cites an average of 15 sources per response, while Gemini cites just three. AI-driven referral traffic to retail sites jumped 1,324% and travel sites 2,215% between October 2024 and May 2026, even as 45% of marketing leaders admitted they can't accurately measure their own AI visibility. News and media saw 82.9% of visibility concentrated among the top three brands in that industry, while finance showed far less concentration at 41.4%.

Why the AI Visibility Index should worry single-platform founders

From the publisher

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Most founders chasing AI search visibility optimize for one engine, usually ChatGPT, because it's the one they use personally. Semrush's data shows that's a losing bet: with only 36 brands visible everywhere and citation patterns diverging by platform, a founder who nails ChatGPT can still be invisible on Gemini or Google AI Mode. The index also found that companies with integrated SEO and AI content teams hit an 81% success rate on visibility goals, versus 36% for teams that keep the functions siloed. For a founder without a dedicated team, that's a case for merging SEO and social content into one calendar instead of running them separately.

  1. Audit your brand across all four AI platforms this week
    Run your company name and your top three competitors through ChatGPT, Gemini, Google AI Mode, and Google's AI Overviews, and screenshot every answer. Semrush's data shows visibility on one platform doesn't transfer to the others, so you need a baseline on all four before you can tell whether any AI search effort is working.
  2. Merge your SEO and social calendars into one workflow
    Integrated teams hit an 81% success rate on AI visibility goals versus 36% for siloed ones, per Semrush. If your SEO writer and your LinkedIn ghostwriter aren't looking at the same content calendar, combine them this week so citation-worthy claims and data points show up in both channels.
  3. Lead your pages with a sourced claim, not a keyword phrase
    ChatGPT alone cites 15 sources per response on average, rewarding pages structured with clear claims, numbers, and named sources. Rewrite your homepage or top landing page this week to open with a specific, sourced claim rather than a headline built around a keyword you're trying to rank for.

By the numbers: AI referral traffic surged 1,324% for retail sites and 2,215% for travel sites between October 2024 and May 2026, per Semrush, even as brand visibility across platforms stays concentrated among a small group of winners.

"Your AI narrative is becoming the decisive entry point to customer experience." — Rachel Thornton, CMO, Adobe, in Semrush's 2026 AI Visibility Index

What to do this week

Pick one platform you haven't checked, likely Gemini or Google AI Mode, and run five customer-language search queries about your category through it this week. Note which competitors get cited and which sources they pull from. If you're not appearing, publish one page this week that answers that exact query in its first two sentences, since Semrush's data shows AI systems favor content that states a claim immediately rather than building up to it.