Semrush study of 126 million prompts shows how differently AI platforms cite

What happened?

Semrush, now part of Adobe, released its 2026 AI Visibility Index on June 26, expanding an earlier 2,500 prompt study to 126 million US AI search prompts collected from January through April 2026. The study tracks how brands get mentioned and cited across ChatGPT, Gemini, Google AI Mode, and Google AI Overviews in 22 industries. Semrush reports big differences between platforms: ChatGPT cited an average of 15 sources per answer, drawing heavily on Reddit and Wikipedia, while Gemini cited an average of 3.

Why does it matter?

Two findings matter for small organizations. First, being mentioned is not the same as being cited: on Gemini, Semrush found the overlap between mentioned brands and cited domains can be as low as 30 percent, so an engine can talk about you without ever pointing to your site. Second, the platforms disagree with each other, so checking your visibility in one engine tells you little about the rest. The study also found visibility far less concentrated in some industries than others, which leaves more room for smaller players in those categories.

Should I do anything?

The full index is free to browse, so start small. Pick the single question your audience most often asks about your kind of organization and run it in both ChatGPT and Gemini. Note whether you are mentioned, whether your site is cited, and which sources each engine leans on. That one comparison shows you the platform differences the study describes, on your own turf. When you are ready for a fuller picture, our visibility audit guide walks the same exercise through every major engine.

Learn more

• Semrush announcement: 2026 AI Visibility Index
• Browse the full index
• Our guide: conduct an AI visibility audit