OpenAI · Model guide
GPT-6 Luna
The most efficient GPT-6 model, built for focused, high-volume tasks. It accepts text and images, supports a 1.05M-token context window, and keeps the family's full reasoning effort range.
What this model is good at
What the vendor positions it for, and which of our models to reach for instead.
VendorThe most efficient GPT-6 model for focused, high-volume tasks.source
- openai/gpt-6-solstronger —Use Sol when complex coding or agentic workflows need more capability.
- openai/gpt-5.6-lunapredecessor —Use GPT-5.6 Luna only for an established compatibility baseline.
Pricing and billing
Tiered pricing: the rate changes once the input passes the threshold.
| Price / 1M tokens by input size | Input < 272.0K | Input ≥ 272.0K |
|---|---|---|
| Input | $ 0.10 | $ 0.20 |
| Output | $ 0.50 | $ 0.75 |
| Cache read | $ 0.010 | $ 0.020 |
| Cache write | $ 0.13 | $ 0.25 |
At this input size you are on the Input < 272.0K tier.
+ 2.0K × $ 0.50
Capabilities and limits
What CrossModel guarantees across every route this model can take right now.
- Context window
- 1.1M tokens
- Max output
- 128.0K tokens
- Input / output modalities
- Text + Image → Text
- Streaming
- Supported
- Tool calling
- Supported
- Structured output (JSON)
- Supported
- Image input
- Supported
- Thinking mode
- Supported· always on
- Reasoning effort
- none · low · medium · high · xhigh · max
- Available endpoints
- /v1/chat/completions · /v1/responses · /v1/messages
Published benchmarks
Scores the vendor reported, with the evaluation setup each one came from.
Vendor-reported numbers, not CrossModel measurements. Scores are only comparable when the benchmark version, metric and evaluation setup match, so nothing here is averaged or ranked.
Use it in your tools
Point the base URL at CrossModel and paste this model ID — every tool below has a setup guide.
Frequently asked questions
What is GPT-6 Luna?
How much does GPT-6 Luna cost?
Does GPT-6 Luna support tool calling and structured output?
Which endpoint do I call?
Can I try it without writing code?
Chat first, integrate later
Chat first, then wire it in once you like the answers.