Model Comparison
GPT-5.6 Sol vs Phi 4Which is better in 2026?
GPT-5.6 Sol significantly outperforms across most benchmarks. Phi 4 is 128.6x cheaper per token.
Verdict: GPT-5.6 Sol vs Phi 4 — which is better?
GPT-5.6 Sol (by OpenAI) and Phi 4 (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-5.6 Sol outperforms in 1 benchmarks (GPQA), while Phi 4 is better at 0 benchmarks. GPT-5.6 Sol significantly outperforms across most benchmarks.
On price, Phi 4 is roughly 128.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.6 Sol also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Choose GPT-5.6 Sol if…
- you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
- you process long inputs — it offers a 1,050,000 token context window
- you want the most recent training data — it shipped Jul 2026
Choose Phi 4 if…
- cost matters — it's about 128.6x cheaper per token
- you need open weights you can self-host or fine-tune
Performance Benchmarks
Comparative analysis across standard metrics
GPT-5.6 Sol outperforms in 1 benchmarks (GPQA), while Phi 4 is better at 0 benchmarks.
GPT-5.6 Sol significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-5.6 Sol ($5.00/1M tokens) is 71.4x more expensive than Phi 4 ($0.07/1M tokens).
For output processing, GPT-5.6 Sol ($30.00/1M tokens) is 214.3x more expensive than Phi 4 ($0.14/1M tokens).
In conclusion, GPT-5.6 Sol is more expensive than Phi 4.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.6 Sol accepts 1,050,000 input tokens compared to Phi 4's 16,000 tokens. GPT-5.6 Sol can generate longer responses up to 128,000 tokens, while Phi 4 is limited to 16,000 tokens.
Input Capabilities
Supported data types and modalities
GPT-5.6 Sol supports multimodal inputs, whereas Phi 4 does not.
GPT-5.6 Sol can handle both text and other forms of data like images, making it suitable for multimodal applications.
GPT-5.6 Sol
Phi 4
License
Usage and distribution terms
GPT-5.6 Sol is licensed under a proprietary license, while Phi 4 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-5.6 Sol was released on 2026-07-09, while Phi 4 was released on 2024-12-12.
GPT-5.6 Sol is 19 months newer than Phi 4.
Jul 9, 2026
1 weeks ago
1.6yr newerDec 12, 2024
1.6 years ago
Knowledge Cutoff
When training data ends
GPT-5.6 Sol has a knowledge cutoff of 2026-02-16, while Phi 4 has a cutoff of 2024-06-01.
GPT-5.6 Sol has more recent training data (up to 2026-02-16), making it potentially better informed about events through that date compared to Phi 4 (2024-06-01).
Feb 2026
1.7 yr newerJun 2024
Provider Availability
GPT-5.6 Sol is available from OpenAI. Phi 4 is available from DeepInfra.
GPT-5.6 Sol
Phi 4
Outputs Comparison
Key Takeaways
GPT-5.6 Sol
View detailsOpenAI
Phi 4
View detailsMicrosoft
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against GPT-5.6 Sol and Phi 4 side-by-side, then vote on the output you prefer.
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FAQ
Common questions about GPT-5.6 Sol vs Phi 4.