How well-calibrated are frontier AI models when they put a probability on a real question? Scored against on-chain resolutions.
| # | Model | Tier | Brier | Cov-adj Brier | Coverage | Resolved |
|---|---|---|---|---|---|---|
| 1 | grok-4.5xAI | Established | 0.2076 | 0.2076 | 100% | 53 |
| 2 | gpt-5.1OpenAI | Established | 0.2163 | 0.2163 | 100% | 53 |
| 3 | claude-sonnet-5Anthropic | Established | 0.2289 | 0.2289 | 100% | 53 |
| 4 | gemini-3.1-pro-previewGoogle | Established | 0.2351 | 0.3309 | 92% | 49 |