High-volume, cost-sensitive work
Choose GPT-5.6 Luna
GPT-5.6 Luna costs 40% less on a typical mix of three input tokens for every output token ($0.45 against $0.75 per million tokens).
GPT-5.6 Luna vs Mistral Large 4: price, context and capabilities
Choose GPT-5.6 Luna for high-volume, cost-sensitive work, writing and code generation and reasoning over long documents. Choose Mistral Large 4 for self-hosting and data control and the latest release.
In short
- GPT-5.6 Luna is 40% cheaper than Mistral Large 4 at the headline price ($0.45 / 1M tokens vs $0.75 / 1M tokens).
- GPT-5.6 Luna reads more per request: 1.05M tokens against 1M.
- Mistral Large 4 is the newer model (October 2026, against Jul 9, 2026).
- Only GPT-5.6 Luna offers reasoning, prompt caching, batch api.
- Only Mistral Large 4 offers self-hostable.
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 $1.50 for Mistral Large 4. Output dominates the bill when answers are long.
Hardest reasoning tasks
Either one
They are practically level on the Artificial Analysis Intelligence Index (37.3 and 38.4).
Reasoning over long documents
Choose GPT-5.6 Luna
GPT-5.6 Luna scores 83.7% on Long-context reasoning (AA-LCR), against 81.3% for Mistral Large 4.
Self-hosting and data control
Choose Mistral Large 4
Mistral Large 4 has open weights, so you can run it on your own servers; GPT-5.6 Luna is only available through its provider.
Latest release
Choose Mistral Large 4
Mistral Large 4 is the newer release (October 2026, against Jul 9, 2026 for GPT-5.6 Luna).
Monthly cost at three volumes
| Volume | GPT-5.6 Luna | Mistral Large 4 | Difference |
|---|---|---|---|
| Prototype: 1M input, 250K output tokens | $0.50 | $0.88 | GPT-5.6 Luna, $0.38 less |
| Production: 20M input, 5M output tokens | $10.00 | $17.50 | GPT-5.6 Luna, $7.50 less |
| Scale: 500M input, 100M output tokens | $220.00 | $400.00 | GPT-5.6 Luna, $180.00 less |
Standard rates, without caching or batch discounts. Volumes are per month.
Specifications side by side
| GPT-5.6 Luna | Mistral Large 4 | |
|---|---|---|
| Provider | OpenAI | Mistral AI |
| Category | Language models | Language models |
| Status | Generally available | Preview |
| Headline price | $0.45 / 1M tokens | $0.75 / 1M tokens |
| Input | $0.20 / 1M tokens | $0.50 / 1M tokens |
| Output | $1.20 / 1M tokens | $1.50 / 1M tokens |
| Cached input | $0.02 / 1M tokens | No data |
| Context window | 1.05M | 1M |
| Max output | 128k | No data |
| Released | Jul 9, 2026 | October 2026 |
| Knowledge cutoff | February 2026 | No data |
| Licence | Proprietary | Open weights |
| Capabilities | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API | Vision, Tool calling, Structured output, Self-hostable |
| API model id | gpt-5.6-luna | mistral-large-4 |
Benchmarks side by side
Leader in bold.
| Benchmark | GPT-5.6 Luna | Mistral Large 4 |
|---|---|---|
| Intelligence Index | 37.3 | 38.4 |
| SciCode | 53.6% | 54.2% |
| Humanity's Last Exam | 39.5% | 35% |
| MMMU-Pro (visual reasoning) | 78.6% | 76.4% |
| Long-context reasoning (AA-LCR) | 83.7% | 81.3% |
| GPQA Diamond | 91.1% | 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 Mistral Large 4?
Choose GPT-5.6 Luna for high-volume, cost-sensitive work, writing and code generation and reasoning over long documents. Choose Mistral Large 4 for self-hosting and data control and the latest release.
Which is cheaper, GPT-5.6 Luna or Mistral Large 4?
GPT-5.6 Luna is 40% cheaper than Mistral Large 4 at the headline price ($0.45 / 1M tokens vs $0.75 / 1M tokens).
Which has the larger context window, GPT-5.6 Luna or Mistral Large 4?
GPT-5.6 Luna reads more per request: 1.05M tokens against 1M.
What is the difference between GPT-5.6 Luna and Mistral Large 4?
GPT-5.6 Luna is made by OpenAI and Mistral Large 4 by Mistral AI. GPT-5.6 Luna is 40% cheaper than Mistral Large 4 at the headline price ($0.45 / 1M tokens vs $0.75 / 1M tokens). GPT-5.6 Luna reads more per request: 1.05M tokens against 1M. Mistral Large 4 is the newer model (October 2026, against Jul 9, 2026). Only GPT-5.6 Luna offers reasoning, prompt caching, batch api. Only Mistral Large 4 offers self-hostable.
How much do GPT-5.6 Luna and Mistral Large 4 cost per month?
At 20 million input and 5 million output tokens a month, GPT-5.6 Luna costs $10.00 and Mistral Large 4 costs $17.50, at standard rates.
Which is newer, GPT-5.6 Luna or Mistral Large 4?
Mistral Large 4 was released on October 2026 and GPT-5.6 Luna on Jul 9, 2026.