Despite major launches from 5+ labs this month， OpenAI occupies most of the token efficiency Pareto frontier

We measure the number of output tokens models produce per task in the Artificial Analysis Intelligence Index. Output tokens consist of answer tokens （can be thought of as how verbose the model is） and reasoning tokens （how much the model thinks before giving an answer）. Reasoning tokens in particular offer a way for models to use compute at inference time to improve responses.

Output tokens are an important determinant of both cost and time per task. Various effort levels of GPT-5.6 Sol dominate the frontier - Terra and Luna produce comparatively more tokens for any level of intelligence.