Weights & Biases — Experiment Tracking for ML

The de-facto standard for logging ML experiments: metrics, configs, and artifacts captured automatically, compared in a dashboard your whole lab can see.

Official Site https://wandb.ai
Category Data
Pricing Freemium
Rating ★★★★☆ (4/5)

Overview

W&B answers ‘which run produced this model, with which hyperparameters?’ permanently: a few lines of code log every metric, config, and artifact to a dashboard where runs are compared, filtered, and shared. Free for academics, integrated with every major ML framework.

Why researchers use it

  • Automatic capture — metrics, gradients, GPU usage, code state per run
  • Run comparison — parallel-coordinate and filter views across hundreds of experiments
  • Academic tier — free team workspaces for research groups

Getting started

  1. pip install wandb; wandb login with a free academic account.
  2. Wrap training: wandb.init(project=…, config=…), then wandb.log({’loss’: loss}).
  3. Use Sweeps for hyperparameter search instead of hand-edited loops.

The honest review

Strengths. The reproducibility ledger every ML paper needs: six months later, the exact config behind Table 2 is one search away. Reports turn runs into shareable supplementary material.

Limitations. Your experiment metadata lives on their cloud (self-hosting exists but is enterprise-priced); logging adds slight overhead; the dashboard invites metric-staring over thinking.

When NOT to use this Classical statistics or a handful of runs don’t need an experiment platform — a results CSV committed to Git is more honest. W&B starts paying at tens of runs and multiple collaborators.