We just released results on Claude Opus 4.1 (Nonthinking) and found that, despite achieving top spots on MMLU Pro and MGSM, the model performs only marginally better across almost all of our benchmarks (<2% performance gain) compared to Claude Opus 4 (Nonthinking).

On our private benchmarks, Opus 4.1 fails to place among the top 10 models. On public benchmarks, however, the model breaks the top 10 on 5 of the 9 public benchmarks we evaluated. This signals the need for more private benchmarks to evaluate meaningful differences between models and gauge true performance.