Verdict
GPT-5.1 leads 6–5 across 12 shared benchmarks.
GPT-5.1 6 · Grok 4.20 5 · 1 tied · higher isn't always better — check the caveats below.
Reported scores — protocols may differ. How we compare
Reasoning: Grok 4.20 leads 2–1 across 3 shared reasoning benchmarks (largest gap: SimpleQA Verified, 48 vs 30.2 — protocols undisclosed).
Context Learning: GPT-5.1 leads 2–0 across 2 shared context learning benchmarks (largest gap: CL-bench Life, 17.3 vs 11.9 — protocols undisclosed).
GPT-5.1 leads 6–5 across 12 shared benchmarks. GPT-5.1 leads 6 benchmarks and Grok 4.20 leads 5, with 1 tied. Higher isn't always better — see the integrity caveats on each benchmark.
GPT-5.1 and Grok 4.20 have 12 benchmarks in common in our data — those are the only rows where a direct, apples-to-apples comparison is drawn.
GPT-5.1 leads context learning 2–0. Grok 4.20 leads reasoning 2–1.