GEO by Engine: How ChatGPT, Claude, Gemini, and Perplexity Choose What to Show
Generative AI has changed how people search for information.
Instead of typing a short keyword into Google and opening several websites, users can now ask complete questions to platforms such as ChatGPT, Claude, Gemini, and Perplexity and receive a conversational answer within seconds.
That creates a new challenge for businesses.
Ranking on Google is still important, but brands also need to understand how their content can become visible, referenced, mentioned, and cited inside AI-generated answers.
This is where Generative Engine Optimization (GEO) becomes important.
However, there is one major misconception: there is no universal GEO formula that works identically across every AI platform.
ChatGPT, Claude, Gemini, and Perplexity have different products, retrieval systems, data sources, and ways of presenting information. Their exact ranking and selection mechanisms are proprietary, so nobody outside the companies operating these systems can provide a complete formula.
What marketers can do is study their publicly documented capabilities, observable behaviour, search experiences, and content requirements — then build content that is useful across these different environments.
In this guide, we will break down how GEO differs across ChatGPT, Claude, Gemini, and Perplexity, what businesses should focus on, and how traditional SEO fits into the AI-search era.