Weights & Biases Freemium

Weights & Biases (W&B) is a platform for tracking machine learning experiments, comparing runs, tuning hyperparameters and managing models from training to deployment. It is free for personal and academic use, with team and enterprise plans billed per seat.

What is Weights & Biases?

W&B is experiment tracking for ML. You add a few lines to your training script (wandb.init() and wandb.log()) and every metric, config and artifact is recorded to a dashboard you can share. Founded in 2017, it has expanded from classic model training into LLM observability with Weave, its eval and tracing tool.

What features does W&B offer?

• Run tracking: log loss, accuracy, learning rates and system metrics automatically, then compare runs side by side.
• Sweeps: run hyperparameter searches (grid, random, Bayesian) with early stopping.
• Artifacts: version datasets and models with lineage so you know which run produced which weights.
• Model Registry: promote models through staging and production with aliases.
• Weave for LLMs: trace prompts, evaluate outputs and monitor production LLM calls.

Weights & Biases highlights

• Free tier with unlimited personal projects and 100GB storage.
• Framework-agnostic: works with PyTorch, TensorFlow, Keras, Hugging Face and scikit-learn.
• Reports and dashboards are shareable links, handy for teams and papers.

What can you use W&B for?

• Tracking training runs across GPU clusters.
• Comparing fine-tuning experiments on the same base model.
• Managing dataset and model versions with full lineage.
• Evaluating LLM outputs with human and automated feedback.
• Writing reproducible reports for research papers.

It is for ML engineers and data scientists who run many experiments and need to compare them. Small one-off scripts do not need it. Team plans get pricey per seat as headcount grows, and the platform is heavy for solo hobbyists who just want a quick plot.

Quick Summary

• Weights & Biases tracks ML experiments and compares runs in a dashboard.
• It includes hyperparameter sweeps, artifacts and a model registry.
• The free tier offers unlimited personal projects and 100GB storage.
• Weave adds LLM tracing and evaluation.
• Best for teams running many experiments, not one-off scripts.