Verdict
GPT-5.4 leads 16–8 across 24 shared benchmarks.
Claude Opus 4.6 8 · GPT-5.4 16 · higher isn't always better — check the caveats below.
Reported scores — protocols may differ. How we compare
Unknown: GPT-5.4 leads 5–2 across 7 shared unknown benchmarks (largest gap: Mystery Game Puzzles, 30.6 vs 17.38 — protocols undisclosed).
Reasoning: Claude Opus 4.6 leads 3–2 across 5 shared reasoning benchmarks (largest gap: DeepResearch Bench, 55.3 vs 35.1 — single evaluator).
Context Learning: GPT-5.4 leads 2–0 across 2 shared context learning benchmarks (largest gap: CL-bench, 27.9 vs 20.7 — protocols undisclosed).
Math: GPT-5.4 leads 2–0 across 2 shared math benchmarks (largest gap: FrontierMath-Tier-4-v2-Private, 49 vs 26.83 — single evaluator).
Vendor claims — compare against the measured scores above. A claim is what a developer says about its own model, not an independent measurement.
Coding
“The new Claude Opus 4.6 improves on its predecessor's coding skills”
No vendor claims on file for GPT-5.4.
GPT-5.4 leads 16–8 across 24 shared benchmarks. Claude Opus 4.6 leads 8 benchmarks and GPT-5.4 leads 16. Higher isn't always better — see the integrity caveats on each benchmark.
Claude Opus 4.6 and GPT-5.4 have 24 benchmarks in common in our data — those are the only rows where a direct, apples-to-apples comparison is drawn.
GPT-5.4 leads unknown 5–2. GPT-5.4 leads context learning 2–0.