Tülu 3 is a series of open-source advanced language models that have been fine-tuned to adapt to various tasks and user needs. These models achieve complex training processes by combining elements of proprietary methods, innovative technology, and established academic research. The success of Tülu 3 is rooted in meticulous data management, rigorous experimentation, innovative methodologies, and enhanced training infrastructure. By openly sharing data, recipes, and findings, Tülu 3 aims to empower the community to explore new and innovative fine-tuning techniques.