GPT-5.6 Luna Pro
$0.20 per 1M input tokens and $1.20 per 1M output tokens · 1.05M context · vision, tools, reasoning, JSON.
Prices checked Oct 21, 2026 · tracked by LLM Cost Index since Oct 21, 2026
Cheaper ways to run the same model: GPT-5.6 Luna Pro (batch) at $0.10 / $0.60 — same model, different service (e.g. batch processing with a delay).
What GPT-5.6 Luna Pro costs per month
Estimated monthly bill for typical workloads, using the cached-input price for repeated context. Try your own numbers in the cost calculator.
| Workload | Per month |
|---|---|
| Customer chatbot 1,000 conversations a day, 8 turns each | $134 |
| Document Q&A (RAG) 500 questions a day over retrieved documents | $25.38 |
| Coding / tool-using agent 200 tasks a day, long tool-heavy contexts | $52.20 |
| Content generation 30 long articles a day | $3.24 |
| Classification / extraction 100,000 short items a day | $234 |
Prompts above 272K tokens are billed at $0.40 input / $1.80 output per 1M.
Price history
We started tracking GPT-5.6 Luna Pro on Oct 21, 2026; the chart appears as soon as there is a second data point. See all recent price changes.
Where to run GPT-5.6 Luna Pro: 5 providers
OpenAI is the cheapest at $0.10 input / $0.60 output per 1M tokens. Uptime is the average over the last 30 days as reported by OpenRouter; see provider reliability.
Cheaper alternatives to GPT-5.6 Luna Pro
Models with the same tool calling, image input, structured output for at least 20% less (3:1 input/output mix), most capable first.
| Model | Input / 1M | Output / 1M | Context | Capabilities |
|---|---|---|---|---|
| Claude Haiku 5.5 Anthropic | $0.10 | $0.50 | 1M | visiontoolsreasoningJSON |
| GLM 5.3 Flash Z.ai | $0.041 | $0.12 | 1.05M | visiontoolsreasoningJSONopen weights |
| GPT-6 Luna OpenAI | $0.10 | $0.50 | 1.05M | visiontoolsreasoningJSON |
| MiMo-V2.6-Flash Xiaomi | $0.14 | $0.28 | 1.05M | visionaudiotoolsreasoningJSONopen weights |
| DeepSeek V4 Flash Vision Exp DeepSeek | $0.216 | $0.647 | 1.05M | visiontoolsreasoningJSONopen weights |
How to pay less for GPT-5.6 Luna Pro
For a customer chatbot (1,000 conversations a day, 8 turns each) that costs $173 a month at list price without caching:
| Option | Per month | You save |
|---|---|---|
| Move to Claude Haiku 5.5 (similar capabilities) | $58.56 | $114 (66%) |
| Switch to GPT-5.6 Luna Pro (batch) | $86.40 | $86.40 (50%) |
| Route to OpenAI (flex tier) | $86.40 | $86.40 (50%) |
| Use prompt caching (60% of input cached) | $134 | $38.88 (22%) |
Other workloads: cut-your-bill tool for GPT-5.6 Luna Pro.
Specifications
| Model ID | openai/gpt-5.6-luna-pro |
| Input | file, image, text |
| Output | text |
| Tool calling | Yes |
| Structured output | Yes |
| Reasoning mode | Yes |
| Open weights | No |
| Knowledge cutoff | 2026-02-16 |
| Released | Jul 9, 2026 |
| Web search | $0.01 per request |
FAQ
- How much does GPT-5.6 Luna Pro cost?
- $0.20 per million input tokens and $1.20 per million output tokens; cached input costs $0.02 per million. Prompts over 272K tokens are billed at $0.40 / $1.80. Prices as of Oct 21, 2026.
- What is the context window of GPT-5.6 Luna Pro?
- 1.05M tokens, with up to 128K output tokens per response.
- Does GPT-5.6 Luna Pro support images, tools and structured output?
- Images as input: yes. Tool calling: yes. Structured (JSON) output: yes. Reasoning mode: yes.
- What are cheaper alternatives to GPT-5.6 Luna Pro?
- Models with the same key capabilities for at least 20% less include Claude Haiku 5.5 ($0.10 / $0.50), GLM 5.3 Flash ($0.041 / $0.12), GPT-6 Luna ($0.10 / $0.50).
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