GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume, latency-sensitive tasks such as chat, classification, and lightweight agentic workflows, providing capable reasoning for...
OpenAI: GPT-5.6 Luna — OpenAI. Context window 1,050,000 tokens. API pricing (per 1M tokens): Input $0.2, Output $1.2. License: Proprietary. LMArena 1,431. GPQA Diamond 91.6%.
| Provider | OpenAI |
|---|---|
| API model ID | openai/gpt-5.6-luna |
| Tier | Frontier |
| Context window | 1,050,000 tokens |
| Max output | 128,000 tokens |
| License | Proprietary |
| API pricing (per 1M tokens) · Input | $0.2 |
| API pricing (per 1M tokens) · Output | $1.2 |
| LMArena | 1,431 (gpt-5.6-luna-xhigh) |
| GPQA Diamond | 91.6% |
LMArena (CC-BY 4.0, best reasoning setting, 2026-10-02) · GPQA Diamond: Epoch AI (CC-BY 4.0)
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