Claude Opus 4.6 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.
Quick verdict: which should you choose?
Choose Claude Opus 4.6 if you need
- ✓Strong performance on nuanced reasoning tasks backed by a 52.9 intelligence index
- ✓High-quality structured outputs and careful safety-aligned responses
- ✓Effective handling of large inputs within a 1,000,000-token context
- ✓Reliable results without preview-stage instability
Choose Gemini 3.1 Pro Preview Custom Tools if you need
- ✓Lower output price of $12 per million tokens versus $25
- ✓Flexible extension via custom tools and strong cross-modal coherence
- ✓Slightly larger 1,048,756-token context window
- ✓Preview access to Google's multimodal tool ecosystem
Verdict
Claude Opus 4.6 leads on documented intelligence (52.9 index), nuanced reasoning, and structured outputs while Gemini 3.1 Pro Preview Custom Tools wins on price ($12 vs $25 per million tokens) and custom-tool extensibility with a marginally larger context window. Both handle million-token multimodal inputs effectively but differ in trade-offs around stability and safety alignment.
Claude Opus 4.6 vs Gemini 3.1 Pro Preview Custom Tools: side by side
| Spec | Claude Opus 4.6 | Gemini 3.1 Pro Preview Custom Tools | Winner |
|---|---|---|---|
| Intelligence | 52.9 | — | Tie |
| Output speed | 40 t/s | — | Tie |
| Output price | $25.00/1M | $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 |
Detailed analysis
Pricing
Winner: Gemini 3.1 Pro Preview Custom ToolsGemini 3.1 Pro Preview Custom Tools lists output at $12 per million tokens while Claude Opus 4.6 is $25 per million tokens. This gives Gemini a clear cost advantage for high-volume use.
Context Window
Winner: Gemini 3.1 Pro Preview Custom ToolsGemini offers 1,048,756 tokens versus Claude's 1,000,000 tokens. Both support very large multimodal inputs effectively though the difference is small.
Reasoning & Outputs
Winner: Claude Opus 4.6Claude provides a documented 52.9 intelligence index plus explicit strengths in nuanced reasoning and high-quality structured outputs. Gemini's intelligence metrics are not reported.
Extensibility
Winner: Gemini 3.1 Pro Preview Custom ToolsGemini emphasizes flexible custom tools while Claude lacks native real-time web access and tool customization in the given facts.
Claude Opus 4.6
Pros
- +Strong performance on nuanced reasoning tasks
- +Careful and safety-aligned responses
- +Effective handling of large inputs
- +High-quality structured outputs
Cons
- –Slower response times on complex queries
- –More conservative on borderline topics
- –No native real-time web access
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
Summary: Claude Opus 4.6 vs Gemini 3.1 Pro Preview Custom Tools
Choose Claude Opus 4.6 when documented reasoning quality, safety alignment, and structured outputs matter most. Choose Gemini 3.1 Pro Preview Custom Tools when lower cost, custom tools, and a marginally larger context are priorities. The decision hinges on whether known performance metrics or pricing plus extensibility drive the use case.
Frequently asked questions
It depends on priorities: Claude Opus 4.6 has a known intelligence index and stronger listed reasoning strengths while Gemini 3.1 Pro Preview Custom Tools is cheaper and offers custom tools.