GPT-6 Sol (Fast)

GPT-6 Sol is part of OpenAI's GPT-6 family, introduced alongside GPT-6 Luna as a faster and more affordable complement to the flagship GPT-6 Astra. According to OpenAI, Sol was trained with similar methods as Astra, carrying forward the advances behind Astra's state-of-the-art performance in professional work, factuality, coding, computer use, and alignment, while shifting the emphasis toward cost efficiency and everyday accessibility. The model represents a deliberate effort to distribute frontier-grade intelligence beyond the top tier, making capable AI practical for a broader range of recurring tasks and applications at scale.

The GPT-6 family, including Sol, is described by OpenAI as leading across the cost–intelligence curve by combining strong capabilities at each tier with infrastructure that delivers them efficiently. OpenAI attributes the lower serving costs to improvements in caching and inference, passing those savings directly to users and customers. As a quality tier beneath Astra, Sol fits workloads where users want Astra's lineage of professional and coding capabilities in a faster, more economical package, without stepping all the way up to the flagship model for routine work.