We conducted a systematic study of citation patterns across ChatGPT, Google AI Overviews, and Perplexity, running identical prompts across each platform and comparing which sources each platform cited. The findings reveal that these platforms are not interchangeable — each has distinct citation preferences that require tailored optimization strategies.
Google AI Overviews
Google AI Overviews shows the tightest correlation with traditional Google Search rankings. The top 3 ranking pages for a query are cited in AI Overviews 68% of the time. This platform rewards existing SEO investment most directly.
ChatGPT
ChatGPT shows the highest diversity in citation sources, drawing from a broader range of domains including social media, forum content, and niche industry publications that rarely appear in Google results. It particularly favors Wikipedia for factual grounding and comprehensive comparison content for product queries.
Perplexity
Perplexity has the strongest recency bias — freshness of content is a primary ranking signal. It also has the highest percentage of direct source citations, making it the platform where traditional citation-building strategies work most directly.