Model Comparison
GPT-5.1 Thinking vs Phi 4 Mini ReasoningWhich is better in 2026?
GPT-5.1 Thinking significantly outperforms across most benchmarks.
Verdict: GPT-5.1 Thinking vs Phi 4 Mini Reasoning — which is better?
GPT-5.1 Thinking (by OpenAI) and Phi 4 Mini Reasoning (by Microsoft) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.
GPT-5.1 Thinking outperforms in 1 benchmarks (GPQA), while Phi 4 Mini Reasoning is better at 0 benchmarks. GPT-5.1 Thinking significantly outperforms across most benchmarks.
Choose GPT-5.1 Thinking if…
- you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
- you want the most recent training data — it shipped Nov 2025
Choose Phi 4 Mini Reasoning if…
- you need open weights you can self-host or fine-tune
Performance Benchmarks
Comparative analysis across standard metrics
GPT-5.1 Thinking outperforms in 1 benchmarks (GPQA), while Phi 4 Mini Reasoning is better at 0 benchmarks.
GPT-5.1 Thinking significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Context Window
Maximum input and output token capacity
Only GPT-5.1 Thinking specifies input context (400,000 tokens). Only GPT-5.1 Thinking specifies output context (128,000 tokens).
Input Capabilities
Supported data types and modalities
GPT-5.1 Thinking supports multimodal inputs, whereas Phi 4 Mini Reasoning does not.
GPT-5.1 Thinking can handle both text and other forms of data like images, making it suitable for multimodal applications.
GPT-5.1 Thinking
Phi 4 Mini Reasoning
License
Usage and distribution terms
GPT-5.1 Thinking is licensed under a proprietary license, while Phi 4 Mini Reasoning uses MIT.
License differences may affect how you can use these models in commercial or open-source projects.
Proprietary
Closed source
MIT
Open weights
Release Timeline
When each model was launched
GPT-5.1 Thinking was released on 2025-11-12, while Phi 4 Mini Reasoning was released on 2025-04-30.
GPT-5.1 Thinking is 7 months newer than Phi 4 Mini Reasoning.
Nov 12, 2025
7 months ago
6mo newerApr 30, 2025
1.2 years ago
Knowledge Cutoff
When training data ends
Phi 4 Mini Reasoning has a documented knowledge cutoff of 2025-02-01, while GPT-5.1 Thinking's cutoff date is not specified.
We can confirm Phi 4 Mini Reasoning's training data extends to 2025-02-01, but cannot make a direct comparison without GPT-5.1 Thinking's cutoff date.
—
Feb 2025
Outputs Comparison
Key Takeaways
Phi 4 Mini Reasoning
View detailsMicrosoft
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against GPT-5.1 Thinking and Phi 4 Mini Reasoning side-by-side, then vote on the output you prefer.
| Feature | | |
|---|
FAQ
Common questions about GPT-5.1 Thinking vs Phi 4 Mini Reasoning.