GPT-5.6 Sol

GPT-5.6 Sol is one of OpenAI's models, occupying the spot in the lineup that's 'reasonably priced and reasonably capable.' Think of it less as a top-shelf omakase and more as a solid everyday set meal.

OpenAI does offer pricier, more powerful models, but the one businesses actually use the most—and spend the most on—is GPT-5.6 Sol. Roughly a quarter of all the tokens OpenAI sells, the units used to count how much text an AI reads or writes, flow through this model, and it accounts for a similarly large share of revenue.

By contrast, rival Anthropic's flagship model, Fable 5, costs far more than GPT-5.6 Sol yet saw lower adoption. This illustrates that businesses tend to favor reasonably priced mid-tier models over expensive flagship ones, and GPT-5.6 Sol stands as the poster child of that trend.

Articles cite GPT-5.6 Sol's 25% token share and 23% revenue share as evidence that 'a cheaper mid-tier model outsells an expensive flagship model.' Note that GPT-5.6 Sol is a distinct model from GPT-5.6 Luna, which had its price cut. The two share similar names but occupy different positions within OpenAI's lineup.