GPT-5.6 Luna API
The cost-optimized tier of the GPT-5.6 family. After OpenAI's July 2026 price cut it is one of the cheapest 1M-context frontier models — ideal for high-volume queries and extraction.
💰 Save up to 70% vs official OpenAI pricingGPT-5.6 Luna — cheaper than the official OpenAI API
Access GPT-5.6 Luna through AI API Hub and pay less per token. Same OpenAI-compatible endpoint, lower cost.
Technical Specifications
| Provider | OpenAI |
| Model Family | GPT-5.6 Luna |
| Release Date | 2026-07 |
| Context Window | 1M |
| Max Output Tokens | 131,072 |
| Input Price | $0.20 / 1M tokens |
| Output Price | $1.20 / 1M tokens |
| Vision Support | Yes ✓ |
| Function Calling | Yes ✓ |
| JSON Mode | No |
| Streaming | Yes ✓ |
| Fine Tuning | Available |
| Status | Active ✓ |
Overview
GPT-5.6 Luna is OpenAI's current gpt56 model, released in 2026-07. The cost-optimized tier of the GPT-5.6 family. After OpenAI's July 2026 price cut it is one of the cheapest 1M-context frontier models — ideal for high-volume queries and extraction.
For developers, the headline numbers are a 1M context window and up to 131,072 output tokens per response — enough headroom for ultra-low cost and 1m context without chunking your input. Priced at $0.20/1M input and $1.20/1M output, it sits in the budget tier — ideal for high-volume pipelines where token cost dominates.
On the capability side, GPT-5.6 Luna exposes 3 features: Vision, Function Calling, Streaming. Fine-tuning is on the table if you need to specialize behavior on your own data. Vision support means you can pass images alongside text, handy for document parsing or UI automation.
The practical appeal of routing GPT-5.6 Luna through AI API Hub is simplicity: one OpenAI-compatible endpoint, USDT & USDC payments, no credit card, and you're calling the API in under 30 seconds — just swap your base URL.
What Makes GPT-5.6 Luna Different
How GPT-5.6 Luna is used
GPT-5.6 Luna is used for agentic workflows combining visual understanding with action — document processing pipelines that extract data and call APIs, visual Q&A systems, and multimodal agents. Tool calling enables it to trigger external functions based on what it sees in images.
Pricing position within OpenAI
GPT-5.6 Luna sits in the middle of OpenAI's pricing at $0.20/1M input — 93% below the lineup average ($0.10 cheapest, $20.00 most expensive). 3 siblings cost less, 11 cost more. This mid-tier positioning makes it a sensible default when you're unsure which variant to pick.
GPT-5.6 Luna's role in the lineup
Within OpenAI's lineup, GPT-5.6 Luna is a mid-tier option — balanced between cost and capability. The gpt56 family has 3 active variants, and GPT-5.6 Luna occupies the lower end. This makes it a safe default for production workloads where you're not sure which tier to pick.
Real-world use cases
Real-world deployments: document processing pipelines (read invoice → extract fields → call accounting API), visual Q&A systems, and multimodal agents that act on what they see. GPT-5.6 Luna handles the full see-decide-act loop in a single model call.
vs sibling models
What makes GPT-5.6 Luna different from sibling models: compared to GPT-5.6 Sol ($4.80/1M more expensive, same 1M context); GPT-5.6 Terra ($1.80/1M more expensive, same 1M context); GPT-5.5 ($4.80/1M more expensive, 256K vs 1M context (smaller)). Choose GPT-5.6 Luna when vision input is needed.
API Examples
Python
from openai import OpenAI
client = OpenAI(
api_key="YOUR_API_KEY",
base_url="https://api.apiyihe.org/v1"
)
response = client.chat.completions.create(
model="gpt-5.6-luna",
messages=[
{"role": "user", "content": "Hello"}
]
)
print(response.choices[0].message.content)JavaScript / Node.js
import OpenAI from "openai";
const client = new OpenAI({
apiKey: process.env.API_KEY,
baseURL: "https://api.apiyihe.org/v1"
});
const response = await client.chat.completions.create({
model: "gpt-5.6-luna",
messages: [
{ role: "user", content: "Hello" }
]
});
console.log(response.choices[0].message.content);cURL
curl https://api.apiyihe.org/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer YOUR_API_KEY" \
-d '{
"model": "gpt-5.6-luna",
"messages": [
{"role": "user", "content": "Hello"}
]
}'Supported Features
| Vision / Image Input | ✅ Supported |
| Audio / Voice Input | ❌ Not Available |
| Function Calling | ✅ Supported |
| JSON Mode | ❌ Not Available |
| Streaming | ✅ Supported |
| Fine-Tuning | ✅ Available |
| Multimodal | ❌ Not Available |
Benchmark Scores
| Benchmark | Score |
|---|---|
| MMLU | Not Publicly Available |
| GPQA | Not Publicly Available |
| SWE-Bench | Not Publicly Available |
| HumanEval | Not Publicly Available |
| GSM8K | Not Publicly Available |
| MATH | Not Publicly Available |
| MMMU | Not Publicly Available |
Pricing History
GPT-5.6 Luna was released in 2026-07 by OpenAI and is currently publicly available via AI API Hub.
Current Pricing: $0.20 per 1M input tokens · $1.20 per 1M output tokens. Pay-as-you-go with no minimum commitment.
Pricing Model: Token-based billing (pay per use). No subscription fees. No hidden costs. Fine-tuning incurs additional costs at training and inference time.
💡 OpenAI occasionally updates pricing. AI API Hub reflects current pricing in real-time. All prices in USD. Pay with USDT or USDC — no currency conversion fees.
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Frequently Asked Questions
What is GPT-5.6 Luna?
GPT-5.6 Luna is OpenAI's current gpt56 model. The cost-optimized tier of the GPT-5.6 family. After OpenAI's July 2026 price cut it is one of the cheapest 1M-context frontier models — ideal for high-volume queries and extraction. It offers a 1M context window and supports Vision, Function Calling, Streaming. You can access it through AI API Hub using USDT or USDC — no credit card required.
How much does GPT-5.6 Luna cost?
GPT-5.6 Luna is priced at $0.20 per 1M input tokens and $1.20 per 1M output tokens, billed pay-as-you-go with no minimum. Through AI API Hub you can start with as little as $5 and scale from there.
GPT-5.6 Luna vs Claude Fable 5?
They're built for different jobs. GPT-5.6 Luna costs $0.20/1M input with a 1M window; Claude Fable 5 runs $10.00/1M input with 1M. GPT-5.6 Luna is the more cost-effective pick and still brings ultra-low cost. See the full side-by-side at /compare/gpt-5.6-luna-vs-claude-fable-5/.
GPT-5.6 Luna context window?
GPT-5.6 Luna has a 1M context window, capable of processing up to 1,048,576 tokens in a single request. Maximum output tokens: 131,072.
Does GPT-5.6 Luna support function calling?
Yes, GPT-5.6 Luna supports function/tool calling, allowing you to define functions that the model can invoke. This enables AI agents, API integrations, and structured data extraction.
Is GPT-5.6 Luna multimodal?
Partially — GPT-5.6 Luna supports vision (image input) but not native audio processing.
GPT-5.6 Luna API rate limits?
GPT-5.6 Luna rate limits: 10K RPM. Higher tier plans offer increased throughput. For high-volume production use, consider OpenAI's faster variant models.
How to access GPT-5.6 Luna API?
Access GPT-5.6 Luna through AI API Hub: (1) Register at api.apiyihe.org/register?aff=8JZC, (2) Deposit USDT/USDC, (3) Get your API key instantly, (4) Use the OpenAI-compatible endpoint https://api.apiyihe.org/v1 with model name "gpt-5.6-luna". Start building in under 30 seconds.