Verdict
Gemini 3.1 Pro leads 17–5 across 24 shared benchmarks.
Claude Opus 4.5 5 · Gemini 3.1 Pro 17 · 2 tied · higher isn't always better — check the caveats below.
Reported scores — protocols may differ. How we compare
Unknown: Gemini 3.1 Pro leads 4–1 across 7 shared unknown benchmarks (largest gap: Mystery Game Puzzles, 27.3 vs 14.08 — single evaluator).
Reasoning: Gemini 3.1 Pro leads 5–1 across 6 shared reasoning benchmarks (largest gap: SimpleQA Verified, 73.5 vs 45.7 — protocols undisclosed).
Game Playing: Gemini 3.1 Pro leads 2–0 across 2 shared game playing benchmarks (largest gap: Chess Puzzles, 52.65 vs 9.51 — protocols undisclosed).
Math: Gemini 3.1 Pro leads 2–0 across 2 shared math benchmarks (largest gap: FrontierMath-Tier-4-v2-Private, 26.83 vs 4.88 — single evaluator).
Vendor claims — compare against the measured scores above. A claim is what a developer says about its own model, not an independent measurement.
No vendor claims on file for Claude Opus 4.5.
Agentic / Tool Use
“Gemini 3.1 Pro was evaluated across a range of benchmarks, including reasoning, multimodal capabilities, agentic tool use, multi-lingual performance, and long-context.”
Multimodal
“a suite of highly capable, natively multimodal reasoning models”
Reasoning
“Gemini 3.1 Pro is Google's most advanced model for complex tasks.”
Gemini 3.1 Pro leads 17–5 across 24 shared benchmarks. Claude Opus 4.5 leads 5 benchmarks and Gemini 3.1 Pro leads 17, with 2 tied. Higher isn't always better — see the integrity caveats on each benchmark.
Claude Opus 4.5 and Gemini 3.1 Pro have 24 benchmarks in common in our data — those are the only rows where a direct, apples-to-apples comparison is drawn.
Gemini 3.1 Pro leads reasoning 5–1. Gemini 3.1 Pro leads unknown 4–1.