A preview of GPT-5.6 Sol, Terra, and Luna | OpenAI Help Center
Learn about eligibility, availability, access, and support during the limited preview of the GPT-5.6 model family. Calls may be recorded to improve OpenAI services. Learn more. OpenAI is beginning a limited preview of GPT-5.6 Sol, our flagship and most capable model, alongside GPT-5.6 Terra, a strong lower-cost option, and GPT-5.6 Luna, our fastest and most cost-efficient model. The GPT-5.6 family advances the frontier on software engineering, computer use, professional knowledge work, scientific research, and cybersecurity. During the preview, Sol, Terra, and Luna are available through the OpenAI API and Codex to a limited group of trusted partners and organizations. GPT-5.6 is not available in ChatGPT during the preview. OpenAI plans to expand availability as soon as possible. We have not announced a general-availability date. To learn more about GPT-5.6 Sol and the GPT-5.6 model family, see our launch announcement: Previewing GPT-5.6 Sol: a next-generation model . The preview is