Ahrefs has published citation data across five major AI search engines showing which domains get mentioned most. Wikipedia, Reddit and YouTube dominate. Grok has a 94 percent error rate and more than 50 percent of Gemini and Grok responses cite fabricated URLs. The data has direct implications for which content signals to prioritise in 2026.
The platform that cites you most reliably is not the one with the largest user base. Knowing which AI engine your specific audience uses determines which citation signals actually matter for your strategy.
Ahrefs has published five separate analyses of which domains are cited most frequently across Grok, Microsoft Copilot, Perplexity, Gemini and Google AI Overviews. The findings are consistent in some areas and alarming in others.
Wikipedia, Reddit and YouTube dominate across every platform. Wikipedia leads ChatGPT at approximately 16 percent of citations. Reddit leads Google AI Overviews and Perplexity. LinkedIn maintains strong citation rates for professional queries across Copilot, AI Mode, ChatGPT and Perplexity.
The accuracy data is more concerning. Grok has the highest error rate at 94 percent. More than 50 percent of Gemini and Grok responses cite fabricated URLs. Perplexity performs best on accuracy with an error rate of 37 percent. ChatGPT sends the most traffic clicks but rarely shows source links. Perplexity sends fewer clicks but cites sources far more visibly.
Grok's error rate in AI search citations — compared to 37% for Perplexity, which has the lowest error rate of the major AI search platforms
Why it matters
For Australian content teams, the Ahrefs data has three practical takeaways. First, the domains that perform well in AI citations are the same ones that perform well in traditional search: high-authority, frequently updated, with clear entity structure. GEO and SEO are not separate disciplines.
Second, the fabricated URL problem means you cannot assume an AI citation to your brand is a real citation. If you are tracking AI mentions, verify that the URLs cited actually exist on your site before reporting them as wins.
Third, the platform split matters. If your audience uses Perplexity, citations matter more than traffic. If your audience uses ChatGPT, being in the training data and on cited reference sites matters more than individual page authority.