📖 The AI Tool Bible

LangSmith vs MLflow

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

 
LangSmith
Evaluation
MLflow
Evaluation
TaglineLangChain's eval + observability platform.Open-source platform for tracking, evaluating, and deploying ML models and LLM applications.
CategoryEvaluationEvaluation
PricingFreemium· Free starter; Plus $39/mo per seatFree· Free and open source (Apache 2.0); managed offering via Databricks
ModelPlatform (any LLM)Multi-model
Editorial score8.7 / 10
Use cases
LLM tracingevalsLangChain integration
llm-evaluationexperiment-trackingprompt-managementagent-observabilitymodel-registry
Pros
  • Tight LangChain integration
  • Strong tracing UX
  • Mature dataset/eval flows
  • Reasonable per-seat pricing
  • 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
Cons
  • Best value if you're on LangChain
  • UI can feel dense
  • 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
Websitewww.langchain.commlflow.org
Pick LangSmith if
  • Tight LangChain integration
  • Strong tracing UX
  • Mature dataset/eval flows
  • Reasonable per-seat pricing
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)