LLM Reference

GPT-5.2 Codex vs Phi-4 Mini Flash Reasoning

GPT-5.2 Codex (2025) and Phi-4 Mini Flash Reasoning (2025) compare a coding-specialized model against a standalone API model. GPT-5.2 Codex ships a 400k-token context window, while Phi-4 Mini Flash Reasoning ships a 128k-token context window. This page treats the result as workflow and deployment fit, not a universal model winner.

Treat this as a product-type comparison: GPT-5.2 Codex is coding-specialized model, while Phi-4 Mini Flash Reasoning is standalone API model. Choose based on workflow fit before reading any benchmark or price row as decisive.

Decision scorecard

Local evidence first
SignalGPT-5.2 CodexPhi-4 Mini Flash Reasoning
Product typeCoding-specialized modelStandalone API model
Best forcustom coding agents, code generation, and tool loopsreasoning-heavy apps
Decision fitCoding, RAG, and AgentsLong context
Context window400k128k
Cheapest output$14/1M tokens-
Provider routes2 tracked1 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose GPT-5.2 Codex when...
  • GPT-5.2 Codex has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • GPT-5.2 Codex has broader tracked provider coverage for fallback and route flexibility.
  • GPT-5.2 Codex uniquely exposes Vision, Multimodal, and JSON / Tool use in local model data.
  • Local decision data tags GPT-5.2 Codex 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.

GPT-5.2 Codex

$4,900

Cheapest tracked route/tier: Vercel AI Gateway

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

GPT-5.2 Codex -> Phi-4 Mini Flash Reasoning
  • No overlapping tracked provider route is sourced for GPT-5.2 Codex and Phi-4 Mini Flash Reasoning; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Vision, Multimodal, and JSON / Tool use before moving production traffic.
Phi-4 Mini Flash Reasoning -> GPT-5.2 Codex
  • No overlapping tracked provider route is sourced for Phi-4 Mini Flash Reasoning and GPT-5.2 Codex; plan for SDK, billing, or endpoint changes.
  • GPT-5.2 Codex adds Vision, Multimodal, and JSON / Tool use in local capability data.

Specs

Specification
Released2025-12-182025-12-01
Context window400k128k
Parameters3.8B
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryMITOSI-approved
OpennessProprietaryOpen source
WeightsNot releasedUnknown
CodeUnknownUnknown
Commercial useCommercial use: conditionalCommercial use: permitted
Knowledge cutoff2025-082025-02

Pricing and availability

Pricing attributeGPT-5.2 CodexPhi-4 Mini Flash Reasoning
Input price$1.75/1M tokens-
Output price$14/1M tokens-
Providers

Capabilities

CapabilityGPT-5.2 CodexPhi-4 Mini Flash Reasoning
VisionYesNo
MultimodalYesNo
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: 2026-06-30. Data sourced from public model cards and provider documentation.