📖 The AI Tool Bible

LangSmith vs Opik

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

 
LangSmith
Evaluation
Opik
Evaluation
TaglineLangChain's eval + observability platform.Open-source LLM observability and evaluation platform for debugging and monitoring AI agents in production.
CategoryEvaluationEvaluation
PricingFreemium· Free starter; Plus $39/mo per seatFreemium· Free open-source self-host; free Cloud tier (no card); Enterprise contact sales
ModelPlatform (any LLM)Multi-model
Editorial score8.7 / 10—
Use cases
LLM tracingevalsLangChain integration
llm-tracingagent-evaluationprompt-testingproduction-monitoringguardrailscost-tracking
Pros
  • Tight LangChain integration
  • Strong tracing UX
  • Mature dataset/eval flows
  • Reasonable per-seat pricing
  • Fully open-source with permissive self-hosting
  • 30+ built-in LLM-as-a-Judge evaluation metrics
  • Broad SDK and framework integrations (LangChain, LlamaIndex, LiteLLM, CrewAI)
  • Production guardrails plus PII protection out of the box
  • Free Cloud tier with no credit card required
Cons
  • Best value if you're on LangChain
  • UI can feel dense
  • Feature surface area is wide; non-trivial onboarding
  • Self-hosting at scale still requires real infra work
  • Ollie auto-fix agent is newer and less battle-tested
  • Cost dashboard is most useful if you're already on Claude Code
Websitewww.langchain.comcomet.com
Pick LangSmith if
  • ✅ Tight LangChain integration
  • ✅ Strong tracing UX
  • ✅ Mature dataset/eval flows
  • ✅ Reasonable per-seat pricing
Pick Opik if
  • ✅ Fully open-source with permissive self-hosting
  • ✅ 30+ built-in LLM-as-a-Judge evaluation metrics
  • ✅ Broad SDK and framework integrations (LangChain, LlamaIndex, LiteLLM, CrewAI)
  • ✅ Production guardrails plus PII protection out of the box
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