Olmo 3 introduces a new set of fully-open language models, available in two sizes: 7 billion and 32 billion parameters. The design focuses on various capabilities essential for modern applications, including long-context reasoning, function calling, coding tasks, instruction following, general conversation, and knowledge recall. This thorough approach to model development includes the complete lifecycle, detailing every stage from initial construction to the final checkpoints and dependencies involved. The standout model in this release is Olmo 3 Think 32B, touted as the most powerful fully-open thinking model available so far. By providing open access to the entire model flow, the creators aim to foster transparency and collaboration within the AI community. This openness allows researchers and developers to explore the model's architecture and improve upon it, potentially leading to advancements in language processing technologies.