Mistral Medium 3.5 vs o4-mini Deep Research
Mistral Medium 3.5 vs o4-mini Deep Research: Mistral Medium 3.5 is cheaper for input-heavy usage ($1.50/M vs $2.00/M input tokens), while Mistral Medium 3.5 is better for long-context tasks (256,000 tokens).
Direct answer: choose Mistral Medium 3.5 for lower token spend and choose Mistral Medium 3.5 when your workload needs longer context.
Compare input and output token pricing, context windows, and monthly cost estimates on one page so you can pick the cheaper model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Mistral Medium 3.5
o4-mini Deep Research
Cost Differences
o4-mini Deep Research costs more than Mistral Medium 3.5
Quick Recommendation
Winner for direct API pricing: Mistral Medium 3.5. At the default workload, Mistral Medium 3.5 saves about $2.25/month ($27.375/year) versus o4-mini Deep Research.
Feature Comparison
| Feature | Mistral Medium 3.5 | o4-mini Deep Research |
|---|---|---|
| Provider | Mistral AI | OpenAI |
| Input Price | $1.50/1M tokens | $2.00/1M tokens |
| Output Price | $7.50/1M tokens | $8.00/1M tokens |
| Context Window | 256,000 tokens | 200,000 tokens |
| Max Output | 32,768 tokens | 32,768 tokens |
| Category | flagship | reasoning |
| Capabilities | textvisioncodereasoning | textreasoningcode |
| Release Date | 4/29/2026 | 6/26/2025 |
Mistral Medium 3.5 vs o4-mini Deep Research: Which Should You Choose?
Choosing between Mistral Medium 3.5 and o4-mini Deep Research depends on your priorities: cost efficiency, context length, or raw capability. Mistral Medium 3.5 is the more affordable option at $1.50/1M input tokens — 25% cheaper than o4-mini Deep Research. Meanwhile, Mistral Medium 3.5 offers a significantly larger context window at 256,000 tokens vs 200,000 for o4-mini Deep Research.
These models come from different providers — Mistral AI and OpenAI — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with Mistral AI, switching to OpenAIinvolves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.
These models target different tiers: Mistral Medium 3.5 is a flagship model while o4-mini Deep Research is reasoning. This means they're optimized for different workloads. Mistral Medium 3.5 is built for complex tasks that require deeper reasoning, while o4-mini Deep Research offers better value for routine operations.
Output costs matter too. Mistral Medium 3.5 charges $7.50/1M output tokens vs $8.00 for o4-mini Deep Research. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Mistral Medium 3.5 has the edge here at $7.50/1M output tokens.
Multimodal capabilities: Mistral Medium 3.5 supports vision (image inputs) while o4-mini Deep Research is text-only. If your application needs image understanding, this narrows your choice.
Best Use Cases
Choose Mistral Medium 3.5 when:
- • Budget is a primary concern
- • You need a larger context window (256,000 tokens)
- • You need more capabilities (vision)
- • You're already using Mistral AI's API ecosystem
Choose o4-mini Deep Research when:
- • You're already using OpenAI's API ecosystem
Pros and Caveats at a Glance
Mistral Medium 3.5
- • Input pricing: $1.50/M tokens
- • Output pricing: $7.50/M tokens
- • Context window: 256,000 tokens
- • Max output: 32,768 tokens
Watch out for
- • Trade-offs are minor in this matchup.
o4-mini Deep Research
- • Input pricing: $2.00/M tokens
- • Output pricing: $8.00/M tokens
- • Context window: 200,000 tokens
- • Max output: 32,768 tokens
Watch out for
- • Higher input cost than Mistral Medium 3.5
- • Higher output cost than Mistral Medium 3.5
- • Smaller context window than Mistral Medium 3.5
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Mistral Medium 3.5 (Mistral AI)
o4-mini Deep Research (OpenAI)
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Sign Up for OpenAI →Frequently Asked Questions
Which is cheaper, Mistral Medium 3.5 or o4-mini Deep Research?▼
What is the context window difference between Mistral Medium 3.5 and o4-mini Deep Research?▼
Which model is better for AI Agent / Agentic Workflows?▼
Which model has better overall pricing for heavy usage?▼
Where can I compare Mistral AI and OpenAI API pricing beyond this model matchup?▼
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