Verdict
GPT-6.1 Sol leads 7–4 across 12 shared benchmarks.
Claude Sonnet 5.5 4 · GPT-6.1 Sol 7 · 1 tied · higher isn't always better — check the caveats below.
Reported scores — protocols may differ. How we compare
Unknown: GPT-6.1 Sol leads 3–1 across 4 shared unknown benchmarks (largest gap: SpireClimb, 24.67 vs 1.33 — protocols undisclosed).
Math: GPT-6.1 Sol leads 1–0 across 2 shared math benchmarks (largest gap: FrontierMath-Tier-4-v2-Private, 100 vs 80.49 — protocols undisclosed).
Reasoning: Evenly split 1–1 across 2 shared reasoning benchmarks (largest gap: SimpleQA Verified, 73.9 vs 46.5 — protocols undisclosed).
GPT-6.1 Sol leads 7–4 across 12 shared benchmarks. Claude Sonnet 5.5 leads 4 benchmarks and GPT-6.1 Sol leads 7, with 1 tied. Higher isn't always better — see the integrity caveats on each benchmark.
Claude Sonnet 5.5 and GPT-6.1 Sol have 12 benchmarks in common in our data — those are the only rows where a direct, apples-to-apples comparison is drawn.
GPT-6.1 Sol leads unknown 3–1. GPT-6.1 Sol leads math 1–0.