BBH (BIG-Bench Hard)
BIG-Bench Hard is a suite of 23 challenging tasks from the BIG-Bench benchmark where language models previously performed below average human raters. Tasks include boolean expressions, causal judgement, date understanding, disambiguation, and more.
Metrics
Accuracy (%) across 23 hard tasks
Created By
Mirac Suzgun et al.
Paper
View paper →Website
Visit website →Top Model Scores
| Rank | Model | Score | Date |
|---|---|---|---|
| 1 | GPT-5.2 | 95.3% | 2026-03 |
| 2 | Claude Opus 4.6 | 94.8% | 2026-02 |
| 3 | Gemini 3 Ultra | 94.1% | 2026-01 |
| 4 | Grok 4 | 92.7% | 2026-02 |
| 5 | Llama 4 405B | 90.6% | 2026-01 |
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