LLM Reference

Gemini 3.1 Flash-Lite vs Phi-4 Reasoning Vision 15B

Gemini 3.1 Flash-Lite (2026) and Phi-4 Reasoning Vision 15B (2026) are general-purpose language models from Google DeepMind and Microsoft Research. Gemini 3.1 Flash-Lite ships a 1.05m-token context window, while Phi-4 Reasoning Vision 15B ships a not-yet-sourced context window. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

Gemini 3.1 Flash-Lite is safer overall; choose Phi-4 Reasoning Vision 15B when vision-heavy evaluation matters.

Decision scorecard

Local evidence first
SignalGemini 3.1 Flash-LitePhi-4 Reasoning Vision 15B
Best formultimodal apps, tool-calling agents, and long-context analysismultimodal apps
Decision fitCoding, RAG, and AgentsVision
Context window1.05m—
Cheapest output$1.50/1M tokens-
Provider routes3 tracked0 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose Gemini 3.1 Flash-Lite when...
  • Gemini 3.1 Flash-Lite has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Gemini 3.1 Flash-Lite has broader tracked provider coverage for fallback and route flexibility.
  • Gemini 3.1 Flash-Lite uniquely exposes JSON / Tool use, Structured outputs, and Code execution in local model data.
  • Local decision data tags Gemini 3.1 Flash-Lite for Coding, RAG, and Agents.
Choose Phi-4 Reasoning Vision 15B when...
  • 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 route or tier on this page.

Gemini 3.1 Flash-Lite

$575

Cheapest tracked route/tier: Google AI Studio

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

Gemini 3.1 Flash-Lite -> Phi-4 Reasoning Vision 15B
  • No overlapping tracked provider route is sourced for Gemini 3.1 Flash-Lite and Phi-4 Reasoning Vision 15B; 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 Reasoning Vision 15B -> Gemini 3.1 Flash-Lite
  • No overlapping tracked provider route is sourced for Phi-4 Reasoning Vision 15B and Gemini 3.1 Flash-Lite; plan for SDK, billing, or endpoint changes.
  • Gemini 3.1 Flash-Lite adds JSON / Tool use, Structured outputs, and Code execution in local capability data.

Specs

Specification
Released2026-05-072026-03-12
Context window1.05m—
Parameters—15B
ArchitectureDecoder Only-
LicenseProprietaryMITOSI-approved
OpennessProprietaryOpen source
WeightsNot releasedUnknown
CodeUnknownUnknown
Commercial useCommercial use: conditionalCommercial use: permitted
Knowledge cutoff2025-012025-03

Pricing and availability

Pricing attributeGemini 3.1 Flash-LitePhi-4 Reasoning Vision 15B
Input price$0.25/1M tokens-
Output price$1.50/1M tokens-
Providers-

Capabilities

CapabilityGemini 3.1 Flash-LitePhi-4 Reasoning Vision 15B
VisionYesYes
MultimodalYesYes
ReasoningNoNo
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.