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Phi-4 14B vs Phi-4 Reasoning Vision 15B

Phi-4 14B (2024) and Phi-4 Reasoning Vision 15B (2026) are general-purpose language models from Microsoft Research. Phi-4 14B ships a not-yet-sourced context window, while Phi-4 Reasoning Vision 15B ships a not-yet-sourced context window. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing. The goal is to make the tradeoff clear before deeper testing.

Phi-4 Reasoning Vision 15B is safer overall; choose Phi-4 14B when provider fit matters.

Decision scorecard

Local evidence first
SignalPhi-4 14BPhi-4 Reasoning Vision 15B
Decision fitClassification and JSON / Tool useVision
Context window
Cheapest output$0.14/1M tokens-
Provider routes3 tracked0 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose Phi-4 14B when...
  • Phi-4 14B has broader tracked provider coverage for fallback and procurement flexibility.
  • Phi-4 14B uniquely exposes Structured outputs in local model data.
  • Local decision data tags Phi-4 14B for Classification and JSON / Tool use.
Choose Phi-4 Reasoning Vision 15B when...
  • Phi-4 Reasoning Vision 15B uniquely exposes Multimodal in local model data.
  • Local decision data tags Phi-4 Reasoning Vision 15B for Vision.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output prices on this page.

Phi-4 14B

$87.00

Cheapest tracked route: OpenRouter

Phi-4 Reasoning Vision 15B

Unavailable

No complete token price in local provider data

Cost delta unavailable until both models have sourced input and output token prices.

Switch friction

Phi-4 14B -> Phi-4 Reasoning Vision 15B
  • No overlapping tracked provider route is sourced for Phi-4 14B and Phi-4 Reasoning Vision 15B; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Structured outputs before moving production traffic.
  • Phi-4 Reasoning Vision 15B adds Multimodal in local capability data.
Phi-4 Reasoning Vision 15B -> Phi-4 14B
  • No overlapping tracked provider route is sourced for Phi-4 Reasoning Vision 15B and Phi-4 14B; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Multimodal before moving production traffic.
  • Phi-4 14B adds Structured outputs in local capability data.

Specs

Specification
Released2024-12-132026-03-12
Context window
Parameters14B15B
Architecturedecoder only-
LicenseOpen SourceMicrosoft Research
Knowledge cutoff--

Pricing and availability

Pricing attributePhi-4 14BPhi-4 Reasoning Vision 15B
Input price$0.07/1M tokens-
Output price$0.14/1M tokens-
Providers-

Capabilities

CapabilityPhi-4 14BPhi-4 Reasoning Vision 15B
VisionNoNo
MultimodalNoYes
ReasoningNoNo
Function callingNoNo
Tool useNoNo
Structured outputsYesNo
Code executionNoNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on multimodal input: Phi-4 Reasoning Vision 15B and structured outputs: Phi-4 14B. 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: Phi-4 14B has $0.07/1M input tokens and Phi-4 Reasoning Vision 15B has no token price sourced yet. Provider availability is 3 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose Phi-4 14B when provider fit and broader provider choice are central to the workload. Choose Phi-4 Reasoning Vision 15B when provider fit 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. For teams standardizing a stack, that distinction is often the difference between a benchmark win and a reliable deployment.

FAQ

Is Phi-4 14B or Phi-4 Reasoning Vision 15B open source?

Phi-4 14B is listed under Open Source. Phi-4 Reasoning Vision 15B is listed under Microsoft Research. 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 multimodal input, Phi-4 14B or Phi-4 Reasoning Vision 15B?

Phi-4 Reasoning Vision 15B 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 structured outputs, Phi-4 14B or Phi-4 Reasoning Vision 15B?

Phi-4 14B has the clearer documented structured outputs signal in this comparison. If structured outputs is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run Phi-4 14B and Phi-4 Reasoning Vision 15B?

Phi-4 14B is available on OpenRouter, Fireworks AI, and Microsoft Foundry. Phi-4 Reasoning Vision 15B is available on the tracked providers still being sourced. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

When should I pick Phi-4 14B over Phi-4 Reasoning Vision 15B?

Phi-4 Reasoning Vision 15B is safer overall; choose Phi-4 14B when provider fit matters. If your workload also depends on provider fit, start with Phi-4 14B; if it depends on provider fit, run the same evaluation with Phi-4 Reasoning Vision 15B.

Continue comparing

Last reviewed: 2026-05-16. Data sourced from public model cards and provider documentation.