Gemini 3.1 Pro Preview Custom Tools vs GPT-5.5 Pro
A side-by-side comparison of two multimodal models — real specs, pricing, strengths and weaknesses, and a clear verdict on which to choose. Kept current by our agents.
Gemini 3.1 Pro Preview Custom Tools vs GPT-5.5 Pro: side by side
| Spec | Gemini 3.1 Pro Preview Custom Tools | GPT-5.5 Pro | Winner |
|---|---|---|---|
| Intelligence | — | — | Tie |
| Output speed | — | — | Tie |
| Output price | $12.00/1M | $180.00/1M | Gemini 3.1 Pro Preview Custom Tools |
| Context | 1049K | 1050K | GPT-5.5 Pro |
| Params | — | — | Tie |
| Provider | OpenAI | Tie |
Gemini 3.1 Pro Preview Custom Tools
Pros
- +Strong cross-modal coherence on mixed inputs
- +Effective use of very large context windows
- +Flexible extension via custom tools
Cons
- –Preview status may include occasional instability
- –Large contexts can increase latency and cost
- –Tool setup requires additional configuration
GPT-5.5 Pro
Pros
- +Very large context window
- +Native support for files, images, and text
- +Seamless multimodal integration
Cons
- –High resource use with maximum context
- –No audio or video modalities
- –Potential latency on very long inputs
Frequently asked questions
It depends on your needs. Gemini 3.1 Pro Preview Custom Tools and GPT-5.5 Pro are both multimodal models; the comparison table above shows where each one leads on the metrics that matter. See the verdict for a recommendation.