📖 The AI Tool Bible

MLflow vs Weights & Biases

A side-by-side look at pricing, capabilities, pros, cons, and our editorial scores.

 
MLflow
Evaluation
Weights & Biases
Evaluation
TaglineOpen-source platform for tracking, evaluating, and deploying ML models and LLM applications.The ML experiment tracker, now with LLM eval features.
CategoryEvaluationEvaluation
PricingFree· Free and open source (Apache 2.0); managed offering via DatabricksFreemium· Free personal; team from $50/mo per seat
ModelMulti-modelPlatform (any LLM)
Editorial score8.4 / 10
Use cases
llm-evaluationexperiment-trackingprompt-managementagent-observabilitymodel-registry
ML experimentsLLM evalWeave
Pros
  • Fully open source under Apache 2.0 with no usage caps
  • Covers eval, tracing, prompts, and registry in one tool
  • Massive ecosystem with 100+ integrations including LangChain and OpenAI
  • Multi-language SDKs (Python, TS, Java, R)
  • Battle-tested at Fortune 500 scale
  • Industry-standard for ML tracking
  • Weave adds LLM-native eval
  • Mature, reliable
  • Strong enterprise features
Cons
  • Self-hosting and ops burden unless you pay for Databricks
  • UI feels engineering-first rather than polished
  • LLM features layered onto a classical-ML core can feel bolted-on
  • Heavier UX than LLM-native tools
  • LLM features still catching up
Websitemlflow.orgwandb.ai
Pick MLflow if
  • Fully open source under Apache 2.0 with no usage caps
  • Covers eval, tracing, prompts, and registry in one tool
  • Massive ecosystem with 100+ integrations including LangChain and OpenAI
  • Multi-language SDKs (Python, TS, Java, R)
Pick Weights & Biases if
  • Industry-standard for ML tracking
  • Weave adds LLM-native eval
  • Mature, reliable
  • Strong enterprise features