OpenAI Ships GPT-5.6 Across Sol, Terra and Luna Tiers

OpenAI has launched GPT-5.6, its most capable model to date, offered in three tiers - Sol for high-volume tasks, Terra for balanced workloads, and Luna for maximum reasoning. The model features adaptive reasoning that automatically allocates more compute to harder problems, native voice and vision, and a context window approaching one million tokens. Priced at $5 input and $30 output per million tokens for the flagship tier, it targets agentic coding, scientific analysis and creative work.