LLM Reference

o3 Mini vs Phi-4 Mini Flash Reasoning

o3 Mini (2025) and Phi-4 Mini Flash Reasoning (2025) are frontier-tier reasoning models from OpenAI and Microsoft Research. o3 Mini 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 o3 Mini when coding workflow support matters.

Decision scorecard

Local evidence first
Signalo3 MiniPhi-4 Mini Flash Reasoning
Best forreasoning-heavy apps, tool-calling agents, and provider-routed productionreasoning-heavy apps
Decision fitCoding, RAG, and AgentsLong context
Context window200k128k
Cheapest output$4.40/1M tokens-
Provider routes4 tracked1 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose o3 Mini when...
  • o3 Mini has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • o3 Mini has broader tracked provider coverage for fallback and route flexibility.
  • o3 Mini uniquely exposes JSON / Tool use, Structured outputs, and Code execution in local model data.
  • Local decision data tags o3 Mini for Coding, RAG, and Agents.
Choose Phi-4 Mini Flash Reasoning when...
  • 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.

o3 Mini

$1,980

Cheapest tracked route/tier: OpenRouter

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

o3 Mini -> Phi-4 Mini Flash Reasoning
  • No overlapping tracked provider route is sourced for o3 Mini and Phi-4 Mini Flash Reasoning; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for JSON / Tool use, Structured outputs, and Code execution before moving production traffic.
Phi-4 Mini Flash Reasoning -> o3 Mini
  • No overlapping tracked provider route is sourced for Phi-4 Mini Flash Reasoning and o3 Mini; plan for SDK, billing, or endpoint changes.
  • o3 Mini adds JSON / Tool use, Structured outputs, and Code execution in local capability data.

Specs

Specification
Released2025-01-312025-12-01
Context window200k128k
Parameters3.8B
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryMITOSI-approved
OpennessProprietaryOpen source
WeightsNot releasedUnknown
CodeUnknownUnknown
Commercial useCommercial use: conditionalCommercial use: permitted
Knowledge cutoff2025-042025-02

Pricing and availability

Pricing attributeo3 MiniPhi-4 Mini Flash Reasoning
Input price$1.10/1M tokens-
Output price$4.40/1M tokens-
Providers

Capabilities

Capabilityo3 MiniPhi-4 Mini Flash Reasoning
VisionNoNo
MultimodalNoNo
ReasoningYesYes
JSON / Tool useYesNo
Structured outputsYesNo
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Continue comparing

Last reviewed: 2026-06-29. Data sourced from public model cards and provider documentation.