High-volume, cost-sensitive work
Choose GPT-5.6 Luna
GPT-5.6 Luna costs 42% less on a typical mix of three input tokens for every output token ($0.45 against $0.78 per million tokens).
GPT-5.6 Luna vs Qwen3.8 27B: price, context and capabilities
Choose GPT-5.6 Luna for high-volume, cost-sensitive work, writing and code generation and reused prompts and documents (RAG, agents). Choose Qwen3.8 27B for the latest release.
In short
- GPT-5.6 Luna is 42% cheaper than Qwen3.8 27B at the headline price ($0.45 / 1M tokens vs $0.775 / 1M tokens).
- GPT-5.6 Luna reads more per request: 1.05M tokens against 1M.
- Qwen3.8 27B is the newer model (Aug 14, 2026, against Jul 9, 2026).
- Only GPT-5.6 Luna offers batch api.
Which should you choose?
Each answer below comes straight from the published prices, specifications and independent benchmark results.
Writing and code generation
Choose GPT-5.6 Luna
GPT-5.6 Luna charges $1.20 per million output tokens, against $2.50 for Qwen3.8 27B. Output dominates the bill when answers are long.
Reused prompts and documents (RAG, agents)
Choose GPT-5.6 Luna
GPT-5.6 Luna charges $0.02 per million cached input tokens, against $0.09 for Qwen3.8 27B.
Latest release
Choose Qwen3.8 27B
Qwen3.8 27B is the newer release (Aug 14, 2026, against Jul 9, 2026 for GPT-5.6 Luna).
Monthly cost at three volumes
| Volume | GPT-5.6 Luna | Qwen3.8 27B | Difference |
|---|---|---|---|
| Prototype: 1M input, 250K output tokens | $0.50 | $0.83 | GPT-5.6 Luna, $0.33 less |
| Production: 20M input, 5M output tokens | $10.00 | $16.50 | GPT-5.6 Luna, $6.50 less |
| Scale: 500M input, 100M output tokens | $220.00 | $350.00 | GPT-5.6 Luna, $130.00 less |
Standard rates, without caching or batch discounts. Volumes are per month.
Specifications side by side
| GPT-5.6 Luna | Qwen3.8 27B | |
|---|---|---|
| Provider | OpenAI | Alibaba Cloud (Qwen) |
| Category | Language models | Language models |
| Status | Generally available | Generally available |
| Headline price | $0.45 / 1M tokens | $0.775 / 1M tokens |
| Input | $0.20 / 1M tokens | $0.20 / 1M tokens |
| Output | $1.20 / 1M tokens | $2.50 / 1M tokens |
| Cached input | $0.02 / 1M tokens | $0.09 / 1M tokens |
| Context window | 1.05M | 1M |
| Max output | 128k | 236k |
| Released | Jul 9, 2026 | Aug 14, 2026 |
| Knowledge cutoff | February 2026 | No data |
| Licence | Proprietary | Proprietary |
| Capabilities | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API | Vision, Reasoning, Tool calling, Structured output, Prompt caching |
| API model id | gpt-5.6-luna | qwen3.8-27b |
Benchmarks side by side
Leader in bold.
| Benchmark | GPT-5.6 Luna | Qwen3.8 27B |
|---|---|---|
| Intelligence Index | 37.3 | No data |
| SciCode | 53.6% | No data |
| GPQA Diamond | 91.1% | No data |
| Humanity's Last Exam | 39.5% | No data |
| MMMU-Pro (visual reasoning) | 78.6% | No data |
| Long-context reasoning (AA-LCR) | 83.7% | No data |
Independent evaluations by Artificial Analysis, run the same way for every model, at the reasoning setting shown. Percentages unless marked as an index.
Frequently asked questions
Should I choose GPT-5.6 Luna or Qwen3.8 27B?
Choose GPT-5.6 Luna for high-volume, cost-sensitive work, writing and code generation and reused prompts and documents (RAG, agents). Choose Qwen3.8 27B for the latest release.
Which is cheaper, GPT-5.6 Luna or Qwen3.8 27B?
GPT-5.6 Luna is 42% cheaper than Qwen3.8 27B at the headline price ($0.45 / 1M tokens vs $0.775 / 1M tokens).
Which has the larger context window, GPT-5.6 Luna or Qwen3.8 27B?
GPT-5.6 Luna reads more per request: 1.05M tokens against 1M.
What is the difference between GPT-5.6 Luna and Qwen3.8 27B?
GPT-5.6 Luna is made by OpenAI and Qwen3.8 27B by Alibaba Cloud (Qwen). GPT-5.6 Luna is 42% cheaper than Qwen3.8 27B at the headline price ($0.45 / 1M tokens vs $0.775 / 1M tokens). GPT-5.6 Luna reads more per request: 1.05M tokens against 1M. Qwen3.8 27B is the newer model (Aug 14, 2026, against Jul 9, 2026). Only GPT-5.6 Luna offers batch api.
How much do GPT-5.6 Luna and Qwen3.8 27B cost per month?
At 20 million input and 5 million output tokens a month, GPT-5.6 Luna costs $10.00 and Qwen3.8 27B costs $16.50, at standard rates.
Which is newer, GPT-5.6 Luna or Qwen3.8 27B?
Qwen3.8 27B was released on Aug 14, 2026 and GPT-5.6 Luna on Jul 9, 2026.