ForecastBench Baseline - Zero-Shot - Overall: leaderboard

ForecastBench Baseline leaderboard, where the ForecastBench team runs models out of the box, zero-shot prompt. Overall index, computed from the averaged dataset and market Brier scores rather than the mean of the two indices; difficulty-adjusted Brier Index on 0-100 (higher is better; 50 equals always forecasting 0.5). Superforecaster and public medians, naive baselines and LLM crowds are excluded.

Metric: Overall Brier Index (difficulty-adjusted, higher is better). Source: www.forecastbench.org. Saturation forecast: Around 2031. 81 models tracked.

Top models

#ModelScoreOverall rank
1Kimi K3 (Max)61#35 (Kimi K3)
2O4 Mini (2025-04-16)60.5#183
3Grok 4.20 0309 (Reasoning)60.5#120 (Grok 4.20 0309)
4Claude Opus 4.1 (20250805)60.5#139
5GPT-4.5 (Preview)60.5#260
6Gemini 2.5 Pro (Preview 03-25)60.4#126
7Grok 4.20 Beta (0309) (Reasoning)60.2#198 (Grok 4.20 Beta (0309))
8GPT-5.5 (2026-04-23)60.2#25
9O3 (2025-04-16)60.1#125
10Claude Sonnet 4.560#148
11GPT-559.9#105
12GLM-559.9#149
13Gemini 3 Pro (Preview)59.8#71
14Gemini 2.5 Flash (Preview 04-17)59.8#246
15Grok 4.359.8#204

No result here: #3 Claude Opus 5.5, #6 GPT-6 Astra, #7 GPT-6.1 Sol.

Interactive version: theaggregate.ai/benchmark?slug=forecastbench-baseline-zero-shot-overall · How It Works · Data refreshed daily, snapshot 2026-11-05.