OpenAI launches GPT-6 Sol and GPT-6 Luna in its API at half the price of the GPT-5.6 generation

On 22 September OpenAI launched GPT-6 Sol and GPT-6 Luna, the smaller members of its GPT-6 family, TechCrunch and VKTR reported. They are separate from GPT-6 Astra, which TechCrunch calls OpenAI's most powerful and capable model yet. Sol is aimed at complex work such as coding; Luna at high-volume, clearly defined jobs such as summarising and extracting.

OpenAI's own pricing page lists GPT-6 Sol at $2 per million input tokens and $10 per million output tokens, against $4 and $20 for GPT-5.6 Sol. GPT-6 Luna is $0.10 and $0.50, against $0.20 and $1.20 for GPT-5.6 Luna. The same page says GPT-5.6 Sol's promotional pricing runs at least through 21 November 2026, and VKTR reported that OpenAI's comparisons with GPT-5.6 are based on that promotional pricing. TechCrunch reported that OpenAI credits better caching and inference for the lower cost.

OpenAI claims Sol makes about half as many errors as its predecessor on an internal test built from conversations where users flagged mistakes, VKTR reported, noting that these are vendor-reported results.

At launch the models were available in the API, ChatGPT Work and Codex, VKTR reported, and ChatGPT's everyday Chat experience did not yet support them.

• Confirmed OpenAI's pricing page lists GPT-6 Sol at $2/$10 and GPT-6 Luna at $0.10/$0.50 per million tokens, against $4/$20 and $0.20/$1.20 for GPT-5.6 Sol and Luna. OpenAI API pricing
• Confirmed “GPT-5.6 Sol's promotional pricing is available at least through November 21, 2026.” OpenAI API pricing
• Reported The GPT-6 models come at half the cost of the GPT-5.6 Sol and Luna series, TechCrunch reported. TechCrunch
• Claimed OpenAI says Sol makes about half as many errors as its predecessor on an internal test, VKTR reported. VKTR