LLM Reference

GPT-4o vs Phi-4 Mini Reasoning

GPT-4o (2024) and Phi-4 Mini Reasoning (2026) are frontier reasoning models from OpenAI and Microsoft Research. GPT-4o ships a 128k-token context window, while Phi-4 Mini Reasoning ships a 128k-token context window. On Google-Proof Q&A, Phi-4 Mini Reasoning leads by 1.4 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

Phi-4 Mini Reasoning is safer overall; choose GPT-4o when coding workflow support matters.

Decision scorecard

Local evidence first
SignalGPT-4oPhi-4 Mini Reasoning
Best formultimodal apps, tool-calling agents, and provider-routed productionreasoning-heavy apps
Decision fitCoding, RAG, and AgentsLong context
Context window128k128k
Cheapest output$10/1M tokens-
Provider routes5 tracked0 tracked
Shared benchmarks1 sharedGoogle-Proof Q&A leader

Decision tradeoffs

Choose GPT-4o when...
  • GPT-4o has broader tracked provider coverage for fallback and procurement flexibility.
  • GPT-4o uniquely exposes Vision, Multimodal, and Function calling in local model data.
  • Local decision data tags GPT-4o for Coding, RAG, and Agents.
Choose Phi-4 Mini Reasoning when...
  • Phi-4 Mini Reasoning holds a shared-benchmark lead on Google-Proof Q&A, ahead by 1.4 points.
  • 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.

GPT-4o

$4,500

Cheapest tracked route/tier: Replicate API

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

GPT-4o -> Phi-4 Mini Reasoning
  • No overlapping tracked provider route is sourced for GPT-4o and Phi-4 Mini Reasoning; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Vision, Multimodal, and Function calling before moving production traffic.
  • Phi-4 Mini Reasoning adds Reasoning in local capability data.
Phi-4 Mini Reasoning -> GPT-4o
  • No overlapping tracked provider route is sourced for Phi-4 Mini Reasoning and GPT-4o; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Reasoning before moving production traffic.
  • GPT-4o adds Vision, Multimodal, and Function calling in local capability data.

Specs

Specification
Released2024-05-132026-05-16
Context window128k128k
Parameters3.8B
ArchitectureDecoder Only-
LicenseProprietaryMITOSI-approved
OpennessProprietaryOpen source
Commercial useCommercial use: conditionalCommercial use: permitted
Knowledge cutoff2023-102025-02

Pricing and availability

Pricing attributeGPT-4oPhi-4 Mini Reasoning
Input price$2.50/1M tokens-
Output price$10/1M tokens-
Providers-

Capabilities

CapabilityGPT-4oPhi-4 Mini Reasoning
VisionYesNo
MultimodalYesNo
ReasoningNoYes
Function callingYesNo
Tool useYesNo
Structured outputsYesNo
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkGPT-4oPhi-4 Mini Reasoning
Google-Proof Q&A50.652.0

Deep dive

On shared benchmark coverage, Google-Proof Q&A has GPT-4o at 50.6 and Phi-4 Mini Reasoning at 52, with Phi-4 Mini Reasoning ahead by 1.4 points. The largest visible gap is 1.4 points on Google-Proof Q&A, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.

The capability footprint differs most on vision: GPT-4o, multimodal input: GPT-4o, reasoning mode: Phi-4 Mini Reasoning, function calling: GPT-4o, tool use: GPT-4o, structured outputs: GPT-4o, and code execution: GPT-4o. 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: GPT-4o has $2.50/1M input tokens and Phi-4 Mini Reasoning has no token price sourced yet. Provider availability is 5 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose GPT-4o when coding workflow support 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.

FAQ

Which has a larger context window, GPT-4o or Phi-4 Mini Reasoning?

GPT-4o supports 128k 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 GPT-4o or Phi-4 Mini Reasoning open source?

GPT-4o 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 vision, GPT-4o or Phi-4 Mini Reasoning?

GPT-4o 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. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, GPT-4o or Phi-4 Mini Reasoning?

GPT-4o 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, GPT-4o 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.

Where can I run GPT-4o and Phi-4 Mini Reasoning?

GPT-4o is available on Replicate API, OpenRouter, Azure OpenAI, OpenAI API, and Vercel AI Gateway. 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.

Continue comparing

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