BIG-Bench Hard
BIG-Bench Hard (BBH) is a subset of 23 challenging BIG-Bench tasks selected because prior language model evaluations did not outperform average human-rater performance. The benchmark contains 6,511 evaluation examples testing various forms of multi-step reasoning including arithmetic, logical reasoning (Boolean expressions, logical deduction), geometric reasoning, temporal reasoning, and language understanding. Tasks require capabilities such as causal judgment, object counting, navigation, pattern recognition, and complex problem solving.
Claude 3.5 Sonnet from Anthropic currently leads the BIG-Bench Hard leaderboard with a score of 0.931 across 21 evaluated AI models.
Claude 3.5 Sonnet leads with 93.1%, followed by Claude 3.5 Sonnet at 93.1% and 
Gemini 1.5 Pro at 89.2%.
Progress Over Time
Interactive timeline showing model performance evolution on BIG-Bench Hard
BIG-Bench Hard Leaderboard
| Context | Cost | License | ||||
|---|---|---|---|---|---|---|
| 1 | Anthropic | — | — | — | ||
| 1 | Anthropic | — | — | — | ||
| 3 | Google | — | — | — | ||
| 4 | Google | 27B | — | — | ||
| 5 | Anthropic | — | — | — | ||
| 6 | Google | 12B | — | — | ||
| 7 | Google | — | — | — | ||
| 8 | Anthropic | — | — | — | ||
| 9 |  Microsoft | 60B | — | — | ||
| 10 | Anthropic | — | — | — | ||
| 11 | Google | 4B | — | — | ||
| 12 | Microsoft | 4B | — | — | ||
| 13 | 8B | — | — | |||
| 13 | 8B | — | — | |||
| 15 | Microsoft | 4B | — | — | ||
| 16 | 7B | — | — | |||
| 17 | 2B | — | — | |||
| 17 | Google | 8B | — | — | ||
| 19 | Google | 8B | — | — | ||
| 19 | 2B | — | — | |||
| 21 | Google | 1B | — | — |
FAQ
Common questions about BIG-Bench Hard.
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