OpenAI launches GPT-6 Sol and Luna with lower API prices

OpenAI introduced GPT-6 Sol and GPT-6 Luna in a company post, expanding its latest model family with faster and cheaper options below GPT-6 Astra. Both models are available through the API as gpt-6-sol and gpt-6-luna.

GPT-6 Sol costs $2 per million input tokens and $10 per million output tokens, half the promotional prices for GPT-5.6 Sol. GPT-6 Luna costs $0.10 per million input tokens and $0.50 per million output tokens, compared with $0.20 and $1.20 for its predecessor.

OpenAI says both models improve professional work, coding, factual accuracy and computer use compared with their GPT-5.6 equivalents. GPT-6 also offers improved prompt caching, including discounts of 90% on cached input token reads and controls that preserve cached context when developers change reasoning effort or tool availability.

GPT-6 Sol and Luna are rolling out in ChatGPT Work and Codex for Plus, Pro, Business, Enterprise and Edu users. Free and Go users can access GPT-6 Luna in the desktop app, while neither model is currently available in Chat.