OpenAI announced GPT-5.6, a new family of models available in three variants: Sol (workhorse), Terra (intermediate), and Luna (budget-friendly).

The company claims the models deliver significant efficiency gains over previous versions, with CEO Sam Altman stating that Sol is 54% more token efficient for AI coding tasks.

OpenAI positions GPT-5.6 as its strongest cybersecurity model yet, supporting defensive activities such as threat modeling, code review, patching, and blue teaming.

The Trump administration previously sought to restrict the model’s rollout over misuse concerns. OpenAI directly benchmarks GPT-5.

6 against Anthropic‘s models using the Artificial Analysis Coding Agent Index, claiming Sol outperforms Anthropic‘s Fable by 2.

8 points while using less than half the output tokens, taking less than half the time, and costing about one-third less. Terra performs just above Fable 5, and Luna outperforms Opus 4.8.

OpenAI also launched ChatGPT Work, a workplace companion for enterprise teams running on desktop, web, and mobile, designed for clerical tasks like drafting documents, spreadsheets, and presentations.

GPT-5.6 is available across ChatGPT, Codex, and the OpenAI API. Pricing per million tokens: Sol at $5 input / $30 output, Terra at $2.50 input / $15 output, and Luna at $1 input / $6 output.