Predictable Scale (Part II) - Farseer: A Refined Scaling Law in LLMs

Abstract

Training Large Language Models (LLMs) is prohibitively expensive, creating a critical scaling gap where insights from small-scale experiments often fail to transfer to resource-intensive production systems, thereby hindering efficient innovation. To bridge this, we introduce Farseer , a novel and refined scaling law offering enhanced predictive accuracy across scales. By systematically constructing a model loss surface L ( N, D ) , Farseer achieves a significantly better fit to empirical data than prior laws (e.g., Chinchilla’s law ). Our methodology yields accurate, robust, and highly generalizable predictions, demonstrating excellent extrapolation capabilities, outperforming Chinchilla’s law, whose extrapolation error is 433% higher. This allows for the reliable evaluation of competing training strategies across all ( N, D ) settings, enabling conclusions from small-scale ablation studies to be confidently extrapolated to predict large-scale performance. Furthermore, Farseer provides new insights into optimal compute allocation, better reflecting the nuanced demands of modern LLM training. To validate our approach, we trained an extensive suite of approximately 1,000 LLMs across diverse scales and configurations, consuming roughly 3 million NVIDIA H100 GPU hours. To foster further research, we are comprehensively open-sourcing all code, data, results 3 , all training logs 4 , all models used in scaling law fitting 5 .