Humanity's Last Exam Diamond
General QA
Humanity's Last Exam Diamond is a fixed 1,000-question revision created by Scale AI and the Center for AI Safety, with 500 reasoning and 500 knowledge questions drawn from HLE and its held-out reserve. The leaderboard reports overall accuracy under closed-book evaluation with automatic answer extraction and judging.
Top models (higher is better)
| Model | Score |
|---|---|
| GPT-6 Astra | 60.6 |
| Claude Opus 5.5 | 55.0 |
| Claude Fable 5.1 | 51.3 |
| Claude Opus 5 | 38.6 |
| Gemini 3.8 Flash | 34.3 |
| GPT-6 Sol | 33.8 |
| GPT-5.6 Sol | 31.2 |
| Muse Spark 1.3 | 25.4 |
| Grok 4.7 | 23.4 |
| Kimi K3 | 22.2 |
| GLM-5.3 | 16.4 |