UnpredictaBench - Code: leaderboard

UnpredictaBench (2026) tests whether LLMs can sample outcomes that follow a target probability distribution rather than collapsing onto one plausible answer. This board is KS@100 on the 238 Code problems, whose distributions are induced by stochastic programs: the percent of problems for which 100 samples from the model, drawn at temperature 1.0 with reasoning off, are not rejected by a two-sample Kolmogorov-Smirnov test against ground-truth samples at p below 0.0001. Higher is better.

Metric: KS@100 (%): share of the 238 Code problems (distributions induced by stochastic programs) for which 100 samples from the model (100 independent calls at temperature 1.0, reasoning effort none, up to 5 retries for a parseable answer) are not rejected by a two-sample Kolmogorov-Smirnov test against ground-truth samples at p < 0.0001; higher is better. Source: arxiv.org. Saturation forecast: Not forecast. 20 models tracked.

Top models

#ModelScoreOverall rank
1GPT-4o29.41#741
2nemotron-3-nano-30B-a3B (Non-reasoning)18.49#1875 (nemotron-3-nano-30B-a3B)
3Ministral-3-3B-Instruct-251217.23#2579
4DeepSeek V3.2 (Non-reasoning)14.29#406 (DeepSeek V3.2)
5Qwen 3.5 2B (Non-reasoning)12.61#4810 (Qwen 3.5 2B)
6GPT-4o Mini10.5#1623
7GPT-5.4 (Non-reasoning)10.5#123 (GPT-5.4)
8Llama 3.1 70B Instruct9.66#1546
9Qwen 3 32B (Non-reasoning)5.46#960 (Qwen 3 32B)
10OLMo 3 7B Instruct5.46#6860
11Grok 4.1 Fast (Non-reasoning)5.46#430 (Grok 4.1 Fast)
12Claude Sonnet 4.65.04#161
13Mistral Large 35.04#817
14Llama 3.1 8B Instruct4.62#4246
15Llama 3.2 1B Instruct4.2#9047

No result here: #1 Claude Fable 5.2, #2 Gemini 4 Carbon, #5 Claude Opus 5.5.

Interactive version: theaggregate.ai/benchmark?slug=unpredictabench-code · How It Works · Data refreshed daily, snapshot 2026-11-13.