OpenAI has rolled out a new family of models under the GPT-5.6 banner, introducing three distinct variants named Sol, Terra, and Luna, each aimed at a different slice of the market.
The full global release to ChatGPT, Codex, and the API went live on July 9, 2026, following a limited preview that kicked off on June 26, 2026, restricted to U.S. government-approved trusted partners.
Three models, three jobs
Sol is the flagship. It is built for heavy lifting: advanced coding, scientific research, and enhanced cybersecurity applications.
Terra sits in the middle. OpenAI positions it as delivering performance comparable to the previous GPT-5.5 generation, but at roughly half the cost.
