Verdict
GPT-6 Astra leads 15–0 across 15 shared benchmarks.
Gemini 3.1 Pro 0 · GPT-6 Astra 15 · higher isn't always better — check the caveats below.
Reported scores — protocols may differ. How we compare
Reasoning: GPT-6 Astra leads 3–0 across 3 shared reasoning benchmarks (largest gap: SimpleQA Verified, 75.6 vs 73.5 — protocols undisclosed).
Unknown: GPT-6 Astra leads 3–0 across 3 shared unknown benchmarks (largest gap: ProofBench, 99 vs 26 — single evaluator).
Coding: GPT-6 Astra leads 2–0 across 2 shared coding benchmarks (largest gap: DeepSWE, 74.12 vs 11.73 — single evaluator).
Math: GPT-6 Astra leads 2–0 across 2 shared math benchmarks (largest gap: FrontierMath-Tier-4-v2-Private, 97.6 vs 26.83 — protocols undisclosed).
Vendor claims — compare against the measured scores above. A claim is what a developer says about its own model, not an independent measurement.
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.”
No vendor claims on file for GPT-6 Astra.
GPT-6 Astra leads 15–0 across 15 shared benchmarks. Gemini 3.1 Pro leads 0 benchmarks and GPT-6 Astra leads 15. Higher isn't always better — see the integrity caveats on each benchmark.
Gemini 3.1 Pro and GPT-6 Astra have 15 benchmarks in common in our data — those are the only rows where a direct, apples-to-apples comparison is drawn.
GPT-6 Astra leads reasoning 3–0. GPT-6 Astra leads unknown 3–0.