GPT-5.6: Frontier intelligence that scales with your ambition

OpenAI launched the GPT-5.6 family on July 9, 2026: Sol (flagship), Terra (balanced), and Luna (cost-efficient). All three support a 1.05M-token context window. GPT-5.6 powers ChatGPT Work and Codex with multi-step reasoning and frontend generation for interactive explanations. Free/Go users access Terra in Work and Codex; Plus+ can choose Sol, Terra, or Luna with effort levels including max and ultra. API offers Programmatic Tool Calling and multi-agent beta. Microsoft 365 Copilot adopts GPT-5.6 as preferred model same day.