SoundnessBench: leaderboard

SoundnessBench (Ho, Liu, Nghiem and Huang, University of Maryland, 2026) gives a model a results-masked research proposal reconstructed from an ICLR 2022-2026 submission and asks it to justify and then classify the proposal's methodological soundness as high or low, against labels from high-agreement reviewer soundness sub-scores (1,099 proposals, 641 high and 458 low). The score is macro-F1 in percent over the two classes under the paper's standard prompt; higher is better.

Metric: Macro-F1 (%; high vs low soundness of 1,099 results-masked ICLR proposals, standard prompt). Source: arxiv.org. Saturation forecast: Around February 2027. 12 models tracked.

Top models

#ModelScoreOverall rank
1GPT-5.469.7#121
2Claude Sonnet 4.665.3#158
3GPT-5.4 Mini63.8#389
4Claude Opus 4.660.5#100
5Gemini 3.1 Pro (Preview)58.4#91
6Qwen 3.5 122B A10B56.3#329
7Qwen 3.5 27B55.1#358
8Gemini 3 Flash54.5#159
9Gemini 2.5 Pro49.8#262
10GPT-4o42.3#741
11Llama 3.3 70B Instruct38.9#1353

No result here: #1 Claude Fable 5.2, #2 Gemini 4 Carbon, #5 Claude Opus 5.5.

Interactive version: theaggregate.ai/benchmark?slug=soundnessbench · How It Works · Data refreshed daily, snapshot 2026-11-12.