GPT-5.1 vs Phi 4 Reasoning Plus
GPT-5.1 leads the LLM Stats Score 36.4 to 15.0.
OpenAI · Microsoft · Updated for 2026
Which is better?
GPT-5.1 leads the overall LLM Stats Score 36.4 to 15.0, ranking #77 overall.
In the 2 individual benchmarks reported for both models, GPT-5.1 wins 2; this is a narrower head-to-head signal than the composite indexes.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT-5.1
- overall performance matters — it scores 36.4 and ranks #77 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- you value its reported benchmark strengths — it wins 2 of 2 exact shared results
- you want the most recent training data — it shipped Nov 2025
Choose Phi 4 Reasoning Plus
- you need open weights you can self-host or fine-tune
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
9 reported for GPT-5.1 · 11 for Phi 4 Reasoning Plus
GPT-5.1 outperforms in 2 benchmarks (AIME 2025, GPQA), while Phi 4 Reasoning Plus is better at 0 benchmarks.
GPT-5.1 significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Context Window
Maximum input and output token capacity
Only GPT-5.1 specifies input context (400,000 tokens). Only GPT-5.1 specifies output context (128,000 tokens).
Input capabilities
Documented input modalities across available providers
GPT-5.1 supports multimodal inputs, whereas Phi 4 Reasoning Plus does not.
GPT-5.1 can handle both text and other forms of data like images, making it suitable for multimodal applications.
GPT-5.1
Phi 4 Reasoning Plus
License
Usage and distribution terms
GPT-5.1 is licensed under a proprietary license, while Phi 4 Reasoning Plus 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 was released on 2025-11-13, while Phi 4 Reasoning Plus was released on 2025-04-30.
GPT-5.1 is 7 months newer than Phi 4 Reasoning Plus.
Nov 13, 2025
10 months ago
6mo newerApr 30, 2025
1.4 years ago
Knowledge Cutoff
When training data ends
GPT-5.1 has a knowledge cutoff of 2024-09-30, while Phi 4 Reasoning Plus has a cutoff of 2025-03-01.
Phi 4 Reasoning Plus has more recent training data (up to 2025-03-01), making it potentially better informed about events through that date compared to GPT-5.1 (2024-09-30).
Sep 2024
Mar 2025
6 mo newerOutputs Comparison
Judge for yourself.
Run your own prompts against GPT-5.1 and Phi 4 Reasoning Plus side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-5.1 vs Phi 4 Reasoning Plus.