Claude Sonnet 4.5 vs Gemini 3.1 Pro Preview Custom Tools
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.
Claude Sonnet 4.5 vs Gemini 3.1 Pro Preview Custom Tools: side by side
| Spec | Claude Sonnet 4.5 | Gemini 3.1 Pro Preview Custom Tools | Winner |
|---|---|---|---|
| Intelligence | — | — | Tie |
| Output speed | — | — | Tie |
| Output price | $15.00/1M | $12.00/1M | Gemini 3.1 Pro Preview Custom Tools |
| Context | 1000K | 1049K | Gemini 3.1 Pro Preview Custom Tools |
| Params | — | — | Tie |
| Type | Proprietary | Proprietary | Tie |
| Provider | Anthropic | Tie |
Claude Sonnet 4.5
Pros
- +Strong safety alignment
- +Reliable handling of large contexts
- +Careful and detailed reasoning
- +Effective multimodal file support
Cons
- –Can be overly cautious with refusals
- –Vision performance varies by image complexity
- –May produce verbose responses
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
Frequently asked questions
It depends on your needs. Claude Sonnet 4.5 and Gemini 3.1 Pro Preview Custom Tools are both multimodal models; the comparison table above shows where each one leads on the metrics that matter. See the verdict for a recommendation.