PostTrainBench: leaderboard

AI R&D automation benchmark: agents get 4 small LLMs, one H100, and 10 hours to improve model performance through post-training. Measures dataset curation, training strategy, and constraint awareness.

Metric: Weighted Avg Score. Source: posttrainbench.com. Saturation forecast: Around 2029. 13 models tracked.

Top models

#ModelScoreOverall rank
1GPT-5.6 Sol (Max)36.23#19 (GPT-5.6 Sol)
2Claude Opus 535.04#12
3Claude Opus 4.8 (High)33.84#37 (Claude Opus 4.8)
4Claude Opus 4.8 (Max)32.9#37 (Claude Opus 4.8)
5Kimi K331.96#30
6GLM-5.2 (Max)31.7#73 (GLM-5.2)
7Claude Opus 4.7 (xHigh)28.56#49 (Claude Opus 4.7)
8GPT-5.5 (xHigh)27.23#31 (GPT-5.5)
9Grok 4.5 (High)23.45#48 (Grok 4.5)
10Gemini 3.1 Pro (Preview)21.99#58
11GPT-5.4 (High)19#79 (GPT-5.4)

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

Interactive version: theaggregate.ai/benchmark?slug=posttrainbench · How It Works · Data refreshed daily, snapshot 2026-10-20.