OpenAI
LLMsReleased
OpenAI's GPT model line. GPT-6 Astra is the current flagship, rolling out after GPT-5.6 Sol, Terra, and Luna.
GPT-6 Astra
ReleasedSeptember 3, 2026
Sources
GPT-6 Astra: A new generation of intelligence ↗
OpenAI introduced GPT-6 Astra as its most capable broadly deployed model, rolling out first to a limited set of organizations and then to ChatGPT paid plans and the API.
As of 2026-09
Safety overview: GPT-6 Astra ↗
OpenAI dated the Astra safety overview September 3, 2026, and said Astra is its first model to reach the Critical cybersecurity capability level.
As of 2026-09
Timeline
GPT-5.6 Sol, Terra, and Luna
July 9, 2026
GPT-6 Astra
September 3, 2026