GPT-5.6 Luna is a model from OpenAI. Its posted API price is $0.20 per 1M input tokens and $1.20 per 1M output tokens, or $0.45 per 1M tokens blending 3 input tokens with 1 output token, unchanged since yesterday, unchanged over the past week and unchanged over the past month. Since Jul 11, 2026 its blended price has ranged from $0.45 to $2.25. It carries 10.4% of OpenAI's API tokens and is one of the 6 models in the OpenAI token price index, $1.84 per 1M tokens today. Of the 30 models in the token index it is the 21st most expensive. At today's H100 rental price of $3.69 per GPU-hour, its break-even throughput is 2,275 tokens per second per GPU. Prices are collected once a day, for each UTC day.