Each topic written the way a person would ask it. Estimated visits = this site's share of that prompt's demand.
ChatGPT named Spiedigitallibrary.org here in only some runs (below our 2-of-5 confidence bar), so these earn no estimated traffic, but they show where it occasionally surfaces this site.
One of the 5 runs for What are the best books for optics?, verbatim.
How often ChatGPT places this site at each position across its prompt topics.
Sites that come up for the same prompts as Spiedigitallibrary.org, ranked by how many topics they share.
ChatGPT doesn't publish prompt data. We measure real demand for each commercial topic from Google search volume, scale it to ChatGPT's user base (about 1 ChatGPT user for every 8 Google searchers), and run each topic through ChatGPT 5 times to record which sites it recommends and in what order. A click-through-by-rank curve splits each topic's demand across the recommended sites. Every figure is a modeled estimate, not measured analytics. Full methodology →