Model Comparison
GPT-5.4 vs Phi-3.5-mini-instructWhich is better in 2026?
GPT-5.4 significantly outperforms across most benchmarks. Phi-3.5-mini-instruct is 56.3x cheaper per token.
Verdict: GPT-5.4 vs Phi-3.5-mini-instruct — which is better?
GPT-5.4 (by OpenAI) and Phi-3.5-mini-instruct (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-5.4 outperforms in 1 benchmarks (GPQA), while Phi-3.5-mini-instruct is better at 0 benchmarks. GPT-5.4 significantly outperforms across most benchmarks.
On price, Phi-3.5-mini-instruct is roughly 56.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.4 also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.
Choose GPT-5.4 if…
- you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
- you process long inputs — it offers a 1,000,000 token context window
- you want the most recent training data — it shipped Mar 2026
Choose Phi-3.5-mini-instruct if…
- cost matters — it's about 56.3x cheaper per token
- you need open weights you can self-host or fine-tune
Performance Benchmarks
Comparative analysis across standard metrics
GPT-5.4 outperforms in 1 benchmarks (GPQA), while Phi-3.5-mini-instruct is better at 0 benchmarks.
GPT-5.4 significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-5.4 ($2.50/1M tokens) is 25.0x more expensive than Phi-3.5-mini-instruct ($0.10/1M tokens).
For output processing, GPT-5.4 ($15.00/1M tokens) is 150.0x more expensive than Phi-3.5-mini-instruct ($0.10/1M tokens).
In conclusion, GPT-5.4 is more expensive than Phi-3.5-mini-instruct.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.4 accepts 1,000,000 input tokens compared to Phi-3.5-mini-instruct's 128,000 tokens. Both models can generate responses up to 128,000 tokens.
Input Capabilities
Supported data types and modalities
GPT-5.4 supports multimodal inputs, whereas Phi-3.5-mini-instruct does not.
GPT-5.4 can handle both text and other forms of data like images, making it suitable for multimodal applications.
GPT-5.4
Phi-3.5-mini-instruct
License
Usage and distribution terms
GPT-5.4 is licensed under a proprietary license, while Phi-3.5-mini-instruct 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-5.4 was released on 2026-03-05, while Phi-3.5-mini-instruct was released on 2024-08-23.
GPT-5.4 is 19 months newer than Phi-3.5-mini-instruct.
Mar 5, 2026
3 months ago
1.5yr newerAug 23, 2024
1.8 years ago
Knowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
GPT-5.4 is available from OpenAI. Phi-3.5-mini-instruct is available from Azure.
GPT-5.4
Phi-3.5-mini-instruct
Outputs Comparison
Key Takeaways
GPT-5.4
View detailsOpenAI
Phi-3.5-mini-instruct
View detailsMicrosoft
Detailed Comparison
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FAQ
Common questions about GPT-5.4 vs Phi-3.5-mini-instruct.