OpenAI has officially unveiled GPT-5.6 Sol, the flagship model in its new GPT-5.6 family, marking one of the company's most significant AI releases to date. The launch introduces three models—Sol, Terra, and Luna—designed to serve different performance, cost, and reasoning needs for developers, businesses, and everyday users.
GPT-5.6 Sol is positioned as OpenAI's most capable model, with major improvements in coding, scientific research, cybersecurity, and complex reasoning tasks. The company says the model can spend more time solving difficult problems through a new "max" reasoning mode, while an additional "ultra" mode uses coordinated sub-agents to tackle long, multi-step workflows more efficiently.