Verdict
GPT-5 leads 5–4 across 9 shared benchmarks.
GLM-5.1 4 · GPT-5 5 · higher isn't always better — check the caveats below.
Reported scores — protocols may differ. How we compare
Reasoning: GPT-5 leads 2–1 across 3 shared reasoning benchmarks (largest gap: SimpleQA Verified, 50.1 vs 34 — protocols undisclosed).
GPT-5 leads 5–4 across 9 shared benchmarks. GLM-5.1 leads 4 benchmarks and GPT-5 leads 5. Higher isn't always better — see the integrity caveats on each benchmark.
GLM-5.1 and GPT-5 have 9 benchmarks in common in our data — those are the only rows where a direct, apples-to-apples comparison is drawn.
GPT-5 leads reasoning 2–1.