LLM Reference

Gemini 1.5 Pro vs Phi-4 Mini Reasoning

Gemini 1.5 Pro (2024) and Phi-4 Mini Reasoning (2026) are frontier reasoning models from Google DeepMind and Microsoft Research. Gemini 1.5 Pro ships a 2m-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. It focuses on practical selection signals rather than broad model-family marketing.

Gemini 1.5 Pro fits 16x more tokens; pick it for long-context work and Phi-4 Mini Reasoning for tighter calls.

Decision scorecard

Local evidence first
SignalGemini 1.5 ProPhi-4 Mini Reasoning
Best forlong-context analysis and provider-routed productionreasoning-heavy apps
Decision fitRAG, Long context, and VisionLong context
Context window2m128k
Cheapest output$5/1M tokens-
Provider routes2 tracked0 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose Gemini 1.5 Pro when...
  • Gemini 1.5 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Gemini 1.5 Pro has broader tracked provider coverage for fallback and procurement flexibility.
  • Gemini 1.5 Pro uniquely exposes Structured outputs in local model data.
  • Local decision data tags Gemini 1.5 Pro for RAG, Long context, and Vision.
Choose Phi-4 Mini Reasoning when...
  • 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.

Gemini 1.5 Pro

$2,250

Cheapest tracked route/tier: GCP Vertex 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

Gemini 1.5 Pro -> Phi-4 Mini Reasoning
  • No overlapping tracked provider route is sourced for Gemini 1.5 Pro and Phi-4 Mini Reasoning; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Structured outputs before moving production traffic.
  • Phi-4 Mini Reasoning adds Reasoning in local capability data.
Phi-4 Mini Reasoning -> Gemini 1.5 Pro
  • No overlapping tracked provider route is sourced for Phi-4 Mini Reasoning and Gemini 1.5 Pro; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Reasoning before moving production traffic.
  • Gemini 1.5 Pro adds Structured outputs in local capability data.

Specs

Specification
Released2024-02-152026-05-16
Context window2m128k
Parameters3.8B
ArchitectureDecoder Only-
LicenseProprietaryMITOSI-approved
OpennessProprietaryOpen source
Commercial useCommercial use: conditionalCommercial use: permitted
Knowledge cutoff2023-112025-02

Pricing and availability

Pricing attributeGemini 1.5 ProPhi-4 Mini Reasoning
Input price$1.25/1M tokens-
Output price$5/1M tokens-
Providers-

Capabilities

CapabilityGemini 1.5 ProPhi-4 Mini Reasoning
VisionNoNo
MultimodalNoNo
ReasoningNoYes
Function callingNoNo
Tool useNoNo
Structured outputsYesNo
Code executionNoNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Deep dive

The capability footprint differs most on reasoning mode: Phi-4 Mini Reasoning and structured outputs: Gemini 1.5 Pro. 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: Gemini 1.5 Pro has $1.25/1M input tokens and Phi-4 Mini Reasoning has no token price sourced yet. Provider availability is 2 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose Gemini 1.5 Pro when long-context analysis, larger context windows, 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. For teams standardizing a stack, that distinction is often the difference between a benchmark win and a reliable deployment.

FAQ

Which has a larger context window, Gemini 1.5 Pro or Phi-4 Mini Reasoning?

Gemini 1.5 Pro supports 2m 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 Gemini 1.5 Pro or Phi-4 Mini Reasoning open source?

Gemini 1.5 Pro is listed under Proprietary. 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 reasoning mode, Gemini 1.5 Pro 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.

Which is better for structured outputs, Gemini 1.5 Pro or Phi-4 Mini Reasoning?

Gemini 1.5 Pro 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 Gemini 1.5 Pro and Phi-4 Mini Reasoning?

Gemini 1.5 Pro is available on GCP Vertex AI and Google AI Studio. 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.

When should I pick Gemini 1.5 Pro over Phi-4 Mini Reasoning?

Gemini 1.5 Pro fits 16x more tokens; pick it for long-context work and Phi-4 Mini Reasoning for tighter calls. If your workload also depends on long-context analysis, start with Gemini 1.5 Pro; if it depends on reasoning depth, run the same evaluation with Phi-4 Mini Reasoning.

Continue comparing

Last reviewed: 2026-06-15. Data sourced from public model cards and provider documentation.