GPT-5.6 Luna Pro is the same underlying model as [GPT-5.6 Luna](https://openrouter.ai/openai/gpt-5.6-luna), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode
| Provider | openai |
|---|---|
| Input price | $0.200 / 1M tokens |
| Output price | $1.20 / 1M tokens |
| Context window | 1050k tokens |
| Max output | 128k tokens |
| Modalities | file, image, text |
| Model ID | openai/gpt-5.6-luna-pro |
A 1,000-token prompt with a 500-token answer on OpenAI: GPT-5.6 Luna Pro costs roughly $0.00080. Use the OpenRouter cost calculator to price your own prompt across 400+ models, or the token counter to measure prompt length first.
PromNest stores your prompt library and lets you run any prompt on OpenAI: GPT-5.6 Luna Pro with your own OpenRouter key — including side-by-side comparison with other models. Browse 1,000+ ready-made prompt templates to start.