OpenAI Explains How Model Size Drives Performance and Naming Conventions

Ted Sanders clarified that OpenAI’s large language models follow a performance hierarchy—Luna < Terra < Sol < Astra—where larger models deliver better accuracy, higher reliability, and richer recall of obscure facts, but at a higher per‑token cost. He explained that version numbers such as 6.1 indicate release order, shared training data or personality traits with other 6.1 models, and a moderate improvement rather than a major leap like a 7.x release.