On September 22, OpenAI announced its new AI models, "GPT-6 Sol" and "GPT-6 Luna." These models leverage the technology of the flagship "GPT-6 Astra" to enhance speed and cost-efficiency, with API pricing reduced by 50% compared to the GPT-5.6 series.
GPT-6 Sol is a high-performance model designed for complex tasks and coding. According to OpenAI, internal factuality evaluations showed approximately half the errors compared to GPT-5.6 Sol, achieving reliability closer to the more expensive Astra.
GPT-6 Luna, on the other hand, is intended for low-cost, high-volume usage. Its API pricing is $0.10 per million input tokens and $0.50 per million output tokens. Sol is priced at $2 for input and $10 for output.
The new models have been made available to ChatGPT Plus, Pro, Business, Enterprise, and Edu users via "ChatGPT Work" and "Codex," but are not yet accessible through the regular "Chat" interface. While there's a possibility they will replace GPT-5.6 in the future, the timing of this rollout remains unknown.
Furthermore, the flagship GPT-6 Astra is also handled differently. For Plus users, it is available only through Work and Codex, not as the top-tier model in the regular Chat interface.
