GPT-6 Luna Pro vs Mistral Small 4: price, context window and capabilities
GPT-6 Luna Pro (openai/gpt-6-luna-pro) from OpenAI and Mistral Small 4 (mistralai/mistral-small-2603) from Mistral are both multimodal language models on the OceanToken API. GPT-6 Luna Pro costs less per token than Mistral Small 4: $0.10 against $0.15 per 1M input tokens (33% less) and $0.50 against $0.60 per 1M output tokens (17% less). GPT-6 Luna Pro has the larger context window: 1.05M tokens (1,050,000) against 262K (262,144) for Mistral Small 4. Both support tool calling, reasoning, structured outputs and image input; only GPT-6 Luna Pro also lists file input.
Side by side
| Spec | GPT-6 Luna Pro | Mistral Small 4 |
|---|---|---|
| Model | GPT-6 Luna Proopenai/ | Mistral Small 4mistralai/ |
| Publisher | OpenAI | Mistral |
| Kind | Text & vision | Text & vision |
| Context window | 1.05M tokens1,050,000 | 262K tokens262,144 |
| Input price | $0.10 / 1M tokens | $0.15 / 1M tokens |
| Output price | $0.50 / 1M tokens | $0.60 / 1M tokens |
| Cached input price | $0.01 / 1M tokens | $0.015 / 1M tokens |
| Cache write price | $0.125 / 1M tokens | – |
| Web search price | $0.01 / search | – |
| Inputs | text, images and files | text and images |
| Outputs | text | text |
| Tool calling | Yes | Yes |
| Reasoning | Yes | Yes |
| Structured outputs | Yes | Yes |
About these prices
Which should you choose?
- Choose GPT-6 Luna Pro to spend less per token: 33% less for input and 17% less for output than Mistral Small 4.
- Choose GPT-6 Luna Pro for the longest inputs: its context window holds 1.05M tokens against 262K for Mistral Small 4.
- Choose GPT-6 Luna Pro if you need file input: Mistral Small 4 does not list it.
- Not sure? Call both with the same OceanToken API key and compare them on your own prompts; each request is billed per use from one prepaid balance.
Get API Key GPT-6 Luna Pro Mistral Small 4
Frequently asked questions
Which is cheaper, GPT-6 Luna Pro or Mistral Small 4?
GPT-6 Luna Pro. GPT-6 Luna Pro costs less per token than Mistral Small 4: $0.10 against $0.15 per 1M input tokens (33% less) and $0.50 against $0.60 per 1M output tokens (17% less). These are OceanToken starting prices per use; the OceanToken console always shows the current price.
Which has the larger context window, GPT-6 Luna Pro or Mistral Small 4?
GPT-6 Luna Pro. GPT-6 Luna Pro has the larger context window: 1.05M tokens (1,050,000) against 262K (262,144) for Mistral Small 4.
Can I call both GPT-6 Luna Pro and Mistral Small 4 with one API key?
Yes. Both are on the OceanToken API at https://api.oceantoken.ai/v1: one API key and one prepaid balance call either model. Send the model id openai/gpt-6-luna-pro or mistralai/mistral-small-2603.
Models and publishers
GPT-6 Luna Pro · Mistral Small 4 · All OpenAI models · All Mistral models
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