GPT 5.6 Luna
gpt-5.6-luna
OpenAI's cost-optimized general-purpose language model designed for high-volume AI workloads, supporting long-context reasoning, multimodal understanding, and agent tooling for enterprise automation, assistants, content generation, and scalable applications.
- Modalities
- Chat
- Starting price
- From $0.9 / 1M out
- Context
- 1.1M context
OpenAI
README
GPT-5.6 Luna is the cost-efficient model in the GPT-5.6 family, optimized for high-volume AI workloads. It provides strong general intelligence, multimodal understanding, long-context processing, and agent capabilities while significantly reducing inference costs compared with higher-tier GPT-5.6 models. citeturn0search0turn0search1
Specifications
| Item | Specification |
|---|---|
| Model | GPT-5.6 Luna |
| Model ID | gpt-5.6-luna |
| Developer | OpenAI |
| Release | July 2026 |
| Input | Text, Image |
| Output | Text |
| Context Window | 1,050,000 Tokens |
| Max Output | 128,000 Tokens |
| Knowledge Cutoff | February 16, 2026 |
| Vision | ✓ Supported |
| Function Calling | ✓ Supported |
| Structured Outputs | ✓ Supported |
| Streaming | ✓ Supported |
| Reasoning Levels | none / low / medium / high / xhigh / max |
| Input Price | $1 / MTok |
| Output Price | $6 / MTok |
Key Capabilities
Cost-efficient intelligence
GPT-5.6 Luna delivers strong general-purpose AI capabilities with significantly improved cost efficiency, making it suitable for large-scale production deployments.
Long-context understanding
With a 1.05M-token context window, Luna can process:
- Large documents
- Enterprise knowledge bases
- Large code repositories
- Long-running workflows
Multimodal AI
Supports:
- Text understanding
- Image analysis
- OCR
- Visual reasoning
- Multimodal applications
Agent capabilities
Supports:
- Function calling
- Responses API
- Web Search
- File Search
- Computer Use
Enabling scalable AI agents and automation workflows.
Recommended Use Cases
- Enterprise AI assistants
- Customer support automation
- Content generation
- Knowledge retrieval
- RAG applications
- Large-scale AI SaaS products
- Workflow automation
- Batch AI processing
- Multi-agent execution systems
Pricing
Token-based pricing
Tiered by input prompt tokens (incl. cache): once over the threshold, the whole request is billed at the higher tier.
| Token Type | Short context ≤272K | Long context >272K |
|---|---|---|
| Input | $0.15$0.2-25% | $0.3$0.4-25% |
| Output | $0.9$1.2-25% | $1.35$1.8-25% |
| Cached input | $0.015$0.02-25% | $0.03$0.04-25% |
| cache_write | $0.1875$0.25-25% | $0.375$0.5-25% |