Verdict
GPT-5 leads 21–0 across 21 shared benchmarks.
GPT-5 21 · o4-mini 0 · higher isn't always better — check the caveats below.
Reported scores — protocols may differ. How we compare
Reasoning: GPT-5 leads 5–0 across 5 shared reasoning benchmarks (largest gap: SimpleQA Verified, 50.6 vs 23.9 — single evaluator).
Math: GPT-5 leads 3–0 across 3 shared math benchmarks (largest gap: FrontierMath-Tier-4-v2-Private, 21.95 vs 4.88 — single evaluator).
GPT-5 leads 21–0 across 21 shared benchmarks. GPT-5 leads 21 benchmarks and o4-mini leads 0. Higher isn't always better — see the integrity caveats on each benchmark.
GPT-5 and o4-mini have 21 benchmarks in common in our data — those are the only rows where a direct, apples-to-apples comparison is drawn.
GPT-5 leads reasoning 5–0. GPT-5 leads math 3–0.