GPT-5.6 Luna Pro
OpenAI's cost-efficient GPT-5.6 tier with a 1M context, vision, reasoning, and tool use for high-volume workloads.
Overview
What is GPT-5.6 Luna Pro
GPT-5.6 Luna Pro is OpenAI's efficient, high-volume tier in the GPT-5.6 family, released in July 2026. It offers a 1M-token context, vision, reasoning, and tool use at a lower per-token cost than Sol and Terra, making it ideal for production workloads that need frontier capability without flagship pricing.
Running it privately on Venice
On Venice, GPT-5.6 Luna Pro runs under an anonymized privacy tier — your prompts are not stored, profiled, or used for training. You get the same OpenAI frontier model with vision, reasoning, and tool use, but without the surveillance footprint of Big-Tech platforms. It is available via the Venice app and API with zero retention.
Assessment
Strengths and limitations
- 1M-token context window and 128K max output, enabling long-document analysis and large codebases.
- Native vision, reasoning, tool use, and web search for multimodal agentic workflows.
- Most cost-efficient GPT-5.6 tier, optimized for high-throughput production workloads.
- Supports structured JSON output and multiple image inputs for reliable integration.
- Closed weights: cannot be self-hosted, fine-tuned, or audited.
- Retains OpenAI content policies; not uncensored, so refusals may occur on sensitive topics.
- Output token cost is steep compared to open-weights rivals on Venice.
- Privacy tier is anonymized, not end-to-end encrypted or TEE-hardened.
Capabilities
What it supports
- Tool use / function calling
- Vision (image input)
- Reasoning
- Web search
- Code-optimized
- Structured output (JSON schema)
- Audio input
- Video input
- Multiple image inputs
- Log probabilities
Specifications
Datasheet
- Maker
- OpenAI
- Released
- July 9, 2026
- License
- Proprietary
- Open weights
- No
- Context window
- 1,000K tokens
- Max output
- 128K tokens
- Capabilities
- Vision, Function calling, Reasoning, Web search
- Privacy on Venice
- Anonymized — prompts not stored
- Available on Venice since
- Jul 2026
API
Call it from your code
Venice exposes an OpenAI-compatible API. Point your base URL at Venice and pass the model id.
curl https://api.venice.ai/api/v1/chat/completions \
-H "Authorization: Bearer $VENICE_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "openai-gpt-56-luna-pro",
"messages": [{ "role": "user", "content": "Explain quantum tunneling simply." }]
}'Pricing
What it costs on Venice
Billed per token on Venice: $1.25 per 1M input tokens and $7.50 per 1M output tokens.
New Venice accounts include a free daily allowance and 500 welcome credits — no credit card required.
Alternatives
How it compares
| Model | Context window | Price (Venice) | Open weights | Best for |
|---|---|---|---|---|
| GPT-5.6 Luna Pro | 1M tokens | $1.25 in · $7.50 out / 1M | No | Efficient high-volume workloads |
| Claude Sonnet 4.6 | 1M tokens | $3.60 in · $18 out / 1M | No | Balanced performance |
| DeepSeek V3.2 | 160K tokens | $0.33 in · $0.48 out / 1M | Yes | Open cheap inference |
| Grok 4.3 | 1M tokens | $1.42 in · $2.83 out / 1M | No | Real-time queries |
The most cost-efficient GPT-5.6 tier with 1M context, vision, and tool use — run privately with zero prompt retention.
Use cases
What it is good for
- 01High-volume API workloads like summarization, classification, and data extraction.
- 02Long-context document Q&A and legal or medical record analysis.
- 03Vision-enabled agents that parse screenshots, charts, and PDFs.
- 04Coding assistance and multi-file repository reasoning.
- 05Structured data generation with guaranteed JSON schema compliance.
Prompting
Getting better results
Mark reusable prompt prefixes for caching to reduce costs on repetitive workflows.
Start with medium reasoning and test one level lower; Luna Pro often maintains quality with fewer tokens.
Use explicit JSON schema constraints when you need structured output.
For vision tasks, upload high-resolution images directly and reference specific regions in your prompt.
Version history
Flagship tier with maximum reasoning capability.
Balanced tier for everyday work.
Current efficient tier optimized for high-volume workloads.
FAQ
Frequently asked questions
GPT-5.6 Luna Pro is OpenAI's efficient, high-volume tier in the GPT-5.6 family, released in July 2026. It delivers a 1M-token context, vision, reasoning, and tool use at a lower per-token cost than the Sol and Terra tiers.
On Venice, GPT-5.6 Luna Pro costs $1.25 per 1M input tokens and $7.50 per 1M output tokens. Cached input is billed at $0.13 per 1M tokens. You pay only for what you use with no subscription required.
No. GPT-5.6 Luna Pro is proprietary closed-source software from OpenAI. Its weights are not available for download, self-hosting, or fine-tuning.
No, it consumes credits on Venice. New accounts receive welcome credits that let you try it before purchasing more.
Luna Pro offers a 1M context and vision at $1.25/$7.50 per 1M tokens, while Claude Sonnet 4.6 costs $3.60/$18 per 1M. Both are closed weights. Choose Luna Pro for cost-efficient long-context and multimodal work; Sonnet 4.6 if you prefer Anthropic's policy tuning.
Yes. On Venice it supports function calling, structured JSON output, web search, and multiple image inputs for building agentic workflows.
Yes. It accepts vision inputs including multiple images, and can reason over charts, screenshots, and documents alongside text.
It can generate up to 128K tokens in a single response, making it suitable for long-form writing and large code generation.
No. Venice runs the model with its original OpenAI weights and safety filters intact. It is not flagged as uncensored, so standard content policies still apply.
Run GPT-5.6 Luna Pro privately
No prompt logging. No data used for training.