Ahrefs: ChatGPT triggers a web search on just 14% of prompts

Ahrefs analyzed 66.6 million free, logged-out ChatGPT-5.6 Luna responses from August and September 2026 and found only 14.4% triggered a web search at all, averaging 1.6 fan-out queries — the sub-queries ChatGPT runs while answering — each. Of the resulting 15 million fan-out queries, 6.8% used the site: operator to search one domain directly, spread across roughly 116,000 sites; apple.com, ikea.com and nike.com topped the list by mentions. That 6.8% sits far below the 76% that a smaller Seer Interactive study measured on a narrower prompt set in September — Ahrefs’ own comparison table attributes the gap to sample scope and prompt mix, not a methodology error in either study.

A second, separate Ahrefs dataset tracking actual citations (2.4 to 3.8 million ChatGPT answers a month, via Brand Radar) confirms the citation collapse this wire has tracked since August at larger scale: Reddit’s share fell from roughly 1 in 5 answers in March to 1 in 43 by late September, an 88% drop, and Wikipedia fell from 1 in 7 to 1 in 35, down 80%. Over the same stretch, the combined citation share of OpenAI’s 17 licensed content partners more than doubled from 7.5% in March to a July peak of 15.8%, before easing to 12.5% by late September. Reddit itself still ranks ninth among the domains ChatGPT searches directly with the site: operator — Ahrefs reads this as the model still fetching Reddit for opinions while citing it less.