OpenAI cuts API prices in half with new GPT-6 models

OpenAI has released updated versions of Sol and Luna, the smaller members of its GPT-6 family, weeks after launching GPT-6 Astra. The company says the new models extend Astra's capabilities by making that intelligence more efficient and accessible.

Sol targets complex work such as coding. Luna, according to OpenAI, suits clerical tasks: high-volume jobs with a clear goal, like summarising documents, extracting information or answering quick questions.

Half the price

The clearest change is on the API side. The 6 series versions of Sol and Luna cost half as much as the 5.6 series, a drop OpenAI attributes to improvements in caching and inference.

The company also claims the models produce more factually accurate answers and make fewer coding errors. According to the announcement, an internal factuality evaluation built from de-identified real conversations in which users flagged model mistakes shows GPT-6 Sol making about half as many mistakes as its predecessor, reaching Astra-level reliability at much lower cost.

OpenAI repeatedly claims in its announcement that Sol and Luna handle tasks substantially better than Anthropic's top models, Fable and Opus. Anthropic released a new version of Opus 5.5 about 90 minutes before OpenAI's launch.

Availability

The new Sol and Luna versions are available in ChatGPT Work and Codex for most paid accounts, and through the ChatGPT API. Luna is also coming to the desktop app and to Free and Go users. OpenAI expects a gradual rollout across the ChatGPT app and website through the day.

Sources: OpenAI announcement.