OpenAI Unveils GPT-5.6 Models With Sol Terra and Luna Variants

OpenAI unveiled its GPT-5.6 family of models on Thursday. The lineup includes three variants: Sol as the workhorse option, Terra as the intermediate model, and Luna as the budget-friendly choice. Sam Altman stated that Sol is 54 percent more token efficient for AI coding tasks.

OpenAI described GPT-5.6 as its strongest cybersecurity model yet, achieving frontier performance with fewer tokens. The models support defensive activities including threat modeling, code review and patching, and blue teaming. OpenAI also released ChatGPT Work, a workplace companion tool for enterprise teams that runs on desktop, web, and mobile.

The tool assists with drafting documents, spreadsheets, and presentations. OpenAI claims Sol sets a new state of the art on the Artificial Analysis Coding Agent Index at 80, which is 2.8 points above Fable 5. The company said Sol uses less than half the output tokens, takes less than half the time, and costs about one-third less than Fable 5.

Terra performs just above Fable 5 on the index, while Luna outperforms Opus 4.8. GPT-5.6 is available across ChatGPT, Codex, and the OpenAI API. Pricing per million tokens is set at $5 input and $30 output for Sol, $2.50 input and $15 output for Terra, and $1 input and $6 output for Luna.

SpaceXAI and Meta released similar AI models this week.