Mistral Small 3.1 24B Instruct vs Phi-4 Mini Reasoning
Mistral Small 3.1 24B Instruct (2025) and Phi-4 Mini Reasoning (2026) are frontier reasoning models from MistralAI and Microsoft Research. Mistral Small 3.1 24B Instruct ships a 128k-token context window, while Phi-4 Mini Reasoning ships a 128k-token context window. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
Phi-4 Mini Reasoning is safer overall; choose Mistral Small 3.1 24B Instruct when vision-heavy evaluation matters.
Decision scorecard
Local evidence first| Signal | Mistral Small 3.1 24B Instruct | Phi-4 Mini Reasoning |
|---|---|---|
| Best for | multimodal apps and provider-routed production | reasoning-heavy apps |
| Decision fit | RAG, Long context, and Vision | Long context |
| Context window | 128k | 128k |
| Cheapest output | $0.30/1M tokens | - |
| Provider routes | 6 tracked | 0 tracked |
| Shared benchmarks | 0 rows | 0 rows |
Decision tradeoffs
- Mistral Small 3.1 24B Instruct has broader tracked provider coverage for fallback and procurement flexibility.
- Mistral Small 3.1 24B Instruct uniquely exposes Vision, Multimodal, and Structured outputs in local model data.
- Local decision data tags Mistral Small 3.1 24B Instruct for RAG, Long context, and Vision.
- Phi-4 Mini Reasoning uniquely exposes Reasoning in local model data.
- Local decision data tags Phi-4 Mini Reasoning for Long context.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Mistral Small 3.1 24B Instruct
$155
Cheapest tracked route/tier: Together AI
Phi-4 Mini Reasoning
Unavailable
No complete token price in local provider data
Cost delta unavailable until both models have sourced input and output token prices.
Switch friction
- No overlapping tracked provider route is sourced for Mistral Small 3.1 24B Instruct and Phi-4 Mini Reasoning; plan for SDK, billing, or endpoint changes.
- Check replacement coverage for Vision, Multimodal, and Structured outputs before moving production traffic.
- Phi-4 Mini Reasoning adds Reasoning in local capability data.
- No overlapping tracked provider route is sourced for Phi-4 Mini Reasoning and Mistral Small 3.1 24B Instruct; plan for SDK, billing, or endpoint changes.
- Check replacement coverage for Reasoning before moving production traffic.
- Mistral Small 3.1 24B Instruct adds Vision, Multimodal, and Structured outputs in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-12-15 | 2026-05-16 |
| Context window | 128k | 128k |
| Parameters | 24B | 3.8B |
| Architecture | dense | - |
| License | Apache 2.0(OSI) | MIT(OSI) |
| Openness | Open source | Open source |
| Commercial use | Commercial use allowed | Commercial use allowed |
| Knowledge cutoff | 2023-10 | 2025-02 |
Pricing and availability
| Pricing attribute | Mistral Small 3.1 24B Instruct | Phi-4 Mini Reasoning |
|---|---|---|
| Input price | $0.10/1M tokens | - |
| Output price | $0.30/1M tokens | - |
| Providers | - |
Capabilities
| Capability | Mistral Small 3.1 24B Instruct | Phi-4 Mini Reasoning |
|---|---|---|
| Vision | Yes | No |
| Multimodal | Yes | No |
| Reasoning | No | Yes |
| Function calling | No | No |
| Tool use | No | No |
| Structured outputs | Yes | No |
| Code execution | No | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on vision: Mistral Small 3.1 24B Instruct, multimodal input: Mistral Small 3.1 24B Instruct, reasoning mode: Phi-4 Mini Reasoning, and structured outputs: Mistral Small 3.1 24B Instruct. Both models share the core language-model surface, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
Pricing coverage is uneven: Mistral Small 3.1 24B Instruct has $0.10/1M input tokens and Phi-4 Mini Reasoning has no token price sourced yet. Provider availability is 6 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.
Choose Mistral Small 3.1 24B Instruct when vision-heavy evaluation and broader provider choice are central to the workload. Choose Phi-4 Mini Reasoning when reasoning depth are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.
FAQ
Which has a larger context window, Mistral Small 3.1 24B Instruct or Phi-4 Mini Reasoning?
Mistral Small 3.1 24B Instruct supports 128k tokens, while Phi-4 Mini Reasoning supports 128k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Is Mistral Small 3.1 24B Instruct or Phi-4 Mini Reasoning open source?
Mistral Small 3.1 24B Instruct is listed under Apache 2.0. Phi-4 Mini Reasoning is listed under MIT. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, Mistral Small 3.1 24B Instruct or Phi-4 Mini Reasoning?
Mistral Small 3.1 24B Instruct has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for multimodal input, Mistral Small 3.1 24B Instruct or Phi-4 Mini Reasoning?
Mistral Small 3.1 24B Instruct has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for reasoning mode, Mistral Small 3.1 24B Instruct or Phi-4 Mini Reasoning?
Phi-4 Mini Reasoning has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run Mistral Small 3.1 24B Instruct and Phi-4 Mini Reasoning?
Mistral Small 3.1 24B Instruct is available on Cloudflare Workers AI, OpenRouter, Fireworks AI, NVIDIA NIM, and Together AI. Phi-4 Mini Reasoning is available on the tracked providers still being sourced. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-22. Data sourced from public model cards and provider documentation.