Claude Haiku 4.5 vs Phi-4 Mini Flash Reasoning
Claude Haiku 4.5 (2025) and Phi-4 Mini Flash Reasoning (2025) are frontier reasoning models from Anthropic and Microsoft Research. Claude Haiku 4.5 ships a 200k-token context window, while Phi-4 Mini Flash 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. It focuses on practical selection signals rather than broad model-family marketing.
Phi-4 Mini Flash Reasoning is safer overall; choose Claude Haiku 4.5 when coding workflow support matters.
Decision scorecard
Local evidence first| Signal | Claude Haiku 4.5 | Phi-4 Mini Flash Reasoning |
|---|---|---|
| Best for | multimodal apps, tool-calling agents, and provider-routed production | reasoning-heavy apps |
| Decision fit | Coding, RAG, and Agents | Long context |
| Context window | 200k | 128k |
| Cheapest output | $4/1M tokens | - |
| Provider routes | 8 tracked | 1 tracked |
| Shared benchmarks | 0 rows | 0 rows |
Decision tradeoffs
- Claude Haiku 4.5 has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Claude Haiku 4.5 has broader tracked provider coverage for fallback and procurement flexibility.
- Claude Haiku 4.5 uniquely exposes Vision, Multimodal, and Function calling in local model data.
- Local decision data tags Claude Haiku 4.5 for Coding, RAG, and Agents.
- Phi-4 Mini Flash Reasoning uniquely exposes Reasoning in local model data.
- Local decision data tags Phi-4 Mini Flash Reasoning for Long context.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Claude Haiku 4.5
$1,640
Cheapest tracked route/tier: AWS Bedrock
Phi-4 Mini Flash 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 Claude Haiku 4.5 and Phi-4 Mini Flash Reasoning; plan for SDK, billing, or endpoint changes.
- Check replacement coverage for Vision, Multimodal, and Function calling before moving production traffic.
- Phi-4 Mini Flash Reasoning adds Reasoning in local capability data.
- No overlapping tracked provider route is sourced for Phi-4 Mini Flash Reasoning and Claude Haiku 4.5; plan for SDK, billing, or endpoint changes.
- Check replacement coverage for Reasoning before moving production traffic.
- Claude Haiku 4.5 adds Vision, Multimodal, and Function calling in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-10-01 | 2025-12-01 |
| Context window | 200k | 128k |
| Parameters | — | 3.8B |
| Architecture | decoder only | decoder only |
| License | Proprietary | MIT(OSI) |
| Openness | Proprietary | Open source |
| Commercial use | Commercial use with conditions | Commercial use allowed |
| Knowledge cutoff | 2025-02 | 2025-02 |
Pricing and availability
| Pricing attribute | Claude Haiku 4.5 | Phi-4 Mini Flash Reasoning |
|---|---|---|
| Input price | $0.80/1M tokens | - |
| Output price | $4/1M tokens | - |
| Providers |
Capabilities
| Capability | Claude Haiku 4.5 | Phi-4 Mini Flash Reasoning |
|---|---|---|
| Vision | Yes | No |
| Multimodal | Yes | No |
| Reasoning | No | Yes |
| Function calling | Yes | No |
| Tool use | Yes | No |
| Structured outputs | Yes | No |
| Code execution | Yes | 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: Claude Haiku 4.5, multimodal input: Claude Haiku 4.5, reasoning mode: Phi-4 Mini Flash Reasoning, function calling: Claude Haiku 4.5, tool use: Claude Haiku 4.5, structured outputs: Claude Haiku 4.5, and code execution: Claude Haiku 4.5. 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: Claude Haiku 4.5 has $0.80/1M input tokens and Phi-4 Mini Flash Reasoning has no token price sourced yet. Provider availability is 8 tracked routes versus 1. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.
Choose Claude Haiku 4.5 when coding workflow support, larger context windows, and broader provider choice are central to the workload. Choose Phi-4 Mini Flash 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.
FAQ
Which has a larger context window, Claude Haiku 4.5 or Phi-4 Mini Flash Reasoning?
Claude Haiku 4.5 supports 200k tokens, while Phi-4 Mini Flash 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 Claude Haiku 4.5 or Phi-4 Mini Flash Reasoning open source?
Claude Haiku 4.5 is listed under Proprietary. Phi-4 Mini Flash 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, Claude Haiku 4.5 or Phi-4 Mini Flash Reasoning?
Claude Haiku 4.5 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, Claude Haiku 4.5 or Phi-4 Mini Flash Reasoning?
Claude Haiku 4.5 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, Claude Haiku 4.5 or Phi-4 Mini Flash Reasoning?
Phi-4 Mini Flash 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 Claude Haiku 4.5 and Phi-4 Mini Flash Reasoning?
Claude Haiku 4.5 is available on Microsoft Foundry, Anthropic, Snowflake Cortex, AWS Bedrock, and GCP Vertex AI. Phi-4 Mini Flash Reasoning is available on NVIDIA NIM. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
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Last reviewed: 2026-05-25. Data sourced from public model cards and provider documentation.