Weights & Biases

Weights & Biases is the machine learning developer platform that has become the standard infrastructure for experiment tracking, model development, and collaborative AI research at the world's most sophisticated AI organizations. Founded in 2017 by Lukas Biewald, Chris Van Pelt, and Shawn Lewis — practitioners who had lived the pain of managing machine learning experiments at scale without adequate tooling — Weights & Biases was built to solve a problem that every ML researcher and engineer faces: the ability to track, compare, visualize, and reproduce experiments across complex multi-run training workflows in a way that enables genuine scientific progress rather than manual notebook chaos. The W&B platform's core experiment tracking capability — which logs metrics, hyperparameters, system resources, model outputs, and custom visualizations in real time during training runs — has been adopted as standard logging infrastructure at organizations including OpenAI, NVIDIA, Samsung, Toyota, and thousands of other enterprises and research institutions worldwide. W&B Reports enables ML teams to create rich interactive research reports combining code, visualizations, and prose narrative, making it possible to share findings, reproduce results, and build institutional knowledge in ways that static documents cannot support. W&B Artifacts provides versioned storage for datasets, models, and evaluation results, creating a complete lineage graph connecting every model to the exact data and code that produced it. Weights & Biases has expanded beyond experiment tracking into a comprehensive MLOps platform: W&B Launch enables one-click job dispatch to cloud compute resources; W&B Sweeps automates hyperparameter optimization across distributed training infrastructure; W&B Registry provides curated model and dataset management for enterprise teams; and W&B Prompts offers purpose-built tooling for logging, debugging, and evaluating large language model application outputs. The platform's integration with every major ML framework, cloud provider, and training infrastructure makes it the connective tissue that holds complex ML workflows together across heterogeneous environments. For any organization serious about building, iterating on, and operating AI systems with scientific rigor and operational reliability, Weights & Biases is the most trusted and most widely adopted ML developer platform in the world.