GPT-5.6 Luna API pricing
GPT-5.6 Luna costs $0.2 per million input tokens and $1.2 per million output tokens. A typical chatbot request (about 1,500 input + 400 output tokens) costs $0.00078, or $0.78 per 1,000 requests.
0 characters0 words0 tokens (GPT o200k)
| Model | Per month |
|---|---|
| GPT-5.6 Luna |
≈ = estimated token count: only OpenAI publishes its tokenizer. Claude counts use Anthropic’s published ratios; use the count_tokens API for an exact number.
GPT-5.6 Luna price per million tokens
USD, OpenAI standard tier. Prices checked on October 28, 2026.
| Token type | Price per 1M | With Batch API |
|---|---|---|
| Input | $0.2 | $0.1 |
| Cached input | $0.02 | $0.01 |
| Output | $1.2 | $0.6 |
Model ID: gpt-5.6-luna · Source: developers.openai.com
What a GPT-5.6 Luna request costs
| Request | Per request | Per 1,000 |
|---|---|---|
| Short chat reply 500 input + 200 output tokens | $0.00034 | $0.34 |
| Chatbot turn with context 1,500 input + 400 output tokens | $0.00078 | $0.78 |
| Document Q&A (RAG) 8,000 input + 500 output tokens | $0.0022 | $2.20 |
| Long-document summary 150,000 input + 2,000 output tokens | $0.03 | $32.40 |
Token counts are measured with GPT's o200k tokenizer and converted for GPT-5.6 Luna (see below). No caching or batch discount.
Similarly priced models
| Model | Chatbot request | vs GPT-5.6 Luna |
|---|---|---|
| GPT-4o mini OpenAI | $0.00047 | −40% |
| GPT-5.4 nano OpenAI | $0.00080 | +3% |
| DeepSeek Flash DeepSeek | $0.00095 | +22% |
| Gemini 3.1 Flash-Lite Google | $0.00099 | +27% |
| GPT-5 mini OpenAI | $0.0012 | +51% |
| Mistral Large 3 Mistral | $0.0014 | +78% |
Frequently asked questions
How much does the GPT-5.6 Luna API cost?
GPT-5.6 Luna costs $0.2 per million input tokens and $1.2 per million output tokens on OpenAI's standard tier. Prices checked on October 28, 2026.
How much does one GPT-5.6 Luna request cost?
A typical chatbot request with about 1,500 input and 400 output tokens costs about $0.00078, or $0.78 per 1,000 requests. Paste your own prompt into the calculator on this page for an exact estimate.
Does GPT-5.6 Luna support prompt caching?
Yes. Cached input costs $0.02 per million tokens, 90% less than regular input.
Does GPT-5.6 Luna have a Batch API discount?
Yes: 50% off for requests sent through the Batch API, which may take up to 24 hours. That makes it $0.1 / $0.6 per million input / output tokens.
How are GPT-5.6 Luna tokens counted?
GPT-5.6 Luna's tokenizer is not published; we use the o200k count, which is close for newer OpenAI models.