Head-to-head
Claude Sonnet 5.5 vs Gemini 3.1 Pro
As of October 25, 2026, Gemini 3.1 Pro leads Claude Sonnet 5.5 on the Analyzer Index, 87.0 to 86.7.
Normalized scores are min-maxed per benchmark across all models we track (0–100). Open the interactive compare view to add benchmarks to the radar chart or pull in more models.
Claude Sonnet 5.5
AnthropicGemini 3.1 Pro
Google| At a glance | Claude Sonnet 5.5 | Gemini 3.1 Pro |
|---|---|---|
| Analyzer Index | 86.7 (5/13) | 87.0 (9/13) |
| Blended price | $4.00/M | $2.25/M |
| Cheapest host | maker's API | maker's API |
| Context | 1.0M | 2.0M |
| Output speed | 101 tok/s | 188 tok/s |
| Time to first token | 1.06 s | 87.47 s |
| Benchmark | Claude Sonnet 5.5 | Gemini 3.1 Pro |
|---|---|---|
Chatbot Arena Elo Arena | ||
SWE-bench Verified SWE-bench | — | |
MMMU-Pro MMMU-Pro | — | |
Output Speed Speed | ||
Time to First Token TTFT | ||
FrontierMath Tiers 1-3 FrontierMath | — | |
SimpleQA Verified SimpleQA | ||
OTIS Mock AIME 2024-2025 OTIS AIME | ||
Humanity's Last Exam HLE | ||
ARC-AGI 2 ARC-AGI 2 | — | |
Terminal-Bench 2 TermBench 2 | — | |
Frontier Composite Frontier | ||
Output Stability Stability | — | |
Format Adherence Format | — | |
Recovery Rate Recovery | — | |
API Success Rate API OK | ||
Safety Handling Safety | — |
Methodology matches the main AI Model Analyzer About page.