OpenAI Introduces GPT-6 Sol and Luna, Cutting Prices in Half Versus Predecessors

OpenAI introduced GPT-6 Sol and GPT-6 Luna, two new models that extend the GPT-6 family below flagship GPT-6 Astra with a much lower price point while retaining most of its quality.

Details

• Positioning: Astra remains “the most intelligent and aligned model in the world,” while Sol and Luna use similar training methods optimized for faster, cheaper deployment; Sol targets demanding professional and coding work, Luna serves lighter everyday tasks at a significantly lower price than Sol
• Pricing: roughly 50% cheaper than their predecessor models — GPT-6 Sol costs $2 per million input tokens and $10 per million output tokens, while GPT-6 Luna costs $0.10 per million input tokens and $0.50 per million output tokens
• Benchmarks: Sol outperforms Claude Opus 5 on AutomationBench at only 9% of the cost, scores 68.8% on DeepSWE v1.1 (within 1.1 points of Claude Fable 5) at roughly 80% lower cost per task, matches Claude Opus 5 on OSWorld 2.0 computer-use benchmarks at roughly 80% lower cost, and cuts factual mistakes by about 50% versus its predecessor
• Availability: Sol and Luna are available now in ChatGPT Work and Codex for Plus, Pro, Business, Enterprise, and Edu users; Luna is also available to Free and Go users via the desktop app; both are accessible via the OpenAI API as gpt-6-sol and gpt-6-luna

What happened next

Sol and Luna fill out the GPT-6 lineup into a three-tier structure — flagship Astra, professional-grade Sol, and budget Luna — arriving alongside prompt-caching improvements aimed at the same cost-conscious, high-volume usage these two models are built for.