GPT-5.6 Luna
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…
Full description at the source- Input price
- per 1M tokens
- Output price
- per 1M tokens
- Context
- 272K128K max output
- Cost / request
- 8K in · 500 out
- Writing Elo
- 1826EQ-Bench creative writing
01Routes and pricing
02Capabilities
- Input
- text
- Output
- text
- Context
- 272K
- Max output
- 128K
ReasoningTool callingStructured outputJSON modeSeeded sampling
03Benchmarks
Creative writing
1825.8 EloEQ-Bench Creative Writing v3EQ-Bench Creative Writing v3Emotional intelligence
1156.3 EloEQ-Bench 4EQ-Bench 4Output speed
External116 tok/s119.93s to first tokenArtificial Analysis04Quick start
Call it with your RProuter key
Any OpenAI-compatible SDK works. Point it at the RProuter base URL from your API keys page and use this model ID.
Catalog source: openrouter.ai · checked 2026-09-16
const response = await client.chat.completions.create({
model: "openai/gpt-5.6-luna",
messages: [{ role: "user", content: "A story begins…" }],
max_tokens: 500,
stream: true,
});
for await (const chunk of response) {
process.stdout.write(chunk.choices[0]?.delta?.content ?? "");
}