Price Per TokenPrice Per Token
Microsoft
Microsoft
vs
OpenAI
OpenAI

Phi-3.5 Mini 128K Instruct vs GPT-5 Mini

A detailed comparison of pricing, benchmarks, and capabilities

Get our weekly newsletter on pricing changes, new releases, and tools.

Join the Price Per Token Community

Key Takeaways

Phi-3.5 Mini 128K Instruct wins:

  • Cheaper input tokens
  • Cheaper output tokens

GPT-5 Mini wins:

  • Larger context window
  • Faster response time
  • Higher intelligence benchmark
  • Better at coding
  • Better at math
  • Supports vision
  • Has reasoning mode
Price Advantage
Phi-3.5 Mini 128K Instruct
Benchmark Advantage
GPT-5 Mini
Context Window
GPT-5 Mini
Speed
GPT-5 Mini

Pricing Comparison

Benchmark Comparison

Context & Performance

Capabilities

Feature Comparison

FeaturePhi-3.5 Mini 128K InstructGPT-5 Mini
Vision (Image Input)
Tool/Function Calls
Reasoning Mode
Audio Input
Audio Output
PDF Input
Prompt Caching
Web Search

License & Release

PropertyPhi-3.5 Mini 128K InstructGPT-5 Mini
LicenseOpen SourceProprietary
AuthorMicrosoftOpenAI
ReleasedUnknownAug 2025

Phi-3.5 Mini 128K Instruct Modalities

Input
Output

GPT-5 Mini Modalities

Input
textimagefile
Output
text

Frequently Asked Questions

Phi-3.5 Mini 128K Instruct has cheaper input pricing at $0.10/M tokens. Phi-3.5 Mini 128K Instruct has cheaper output pricing at $0.10/M tokens.
Phi-3.5 Mini 128K Instruct has a 128,000 token context window, while GPT-5 Mini has a 400,000 token context window.
Phi-3.5 Mini 128K Instruct does not support vision. GPT-5 Mini supports vision.