📖 The AI Tool Bible

Promptfoo vs Weights & Biases

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

 
Promptfoo
Evaluation
Weights & Biases
Evaluation
TaglineOpen-source eval and red-teaming framework for LLM apps, prompts, and RAG pipelines.The ML experiment tracker, now with LLM eval features.
CategoryEvaluationEvaluation
PricingFreemium· Open-source free; Enterprise SaaS contact salesFreemium· Free personal; team from $50/mo per seat
ModelMulti-modelPlatform (any LLM)
Editorial score—8.4 / 10
Use cases
llm-evalsred-teamingprompt-regressionrag-testingai-securityci-cd-guardrails
ML experimentsLLM evalWeave
Pros
  • Genuinely open source and self-hostable, not a fake-OSS funnel
  • Model-agnostic; works across OpenAI, Anthropic, local, custom APIs
  • Red-teaming covers prompt injection, jailbreaks, PII, policy violations
  • Clean CI integration with GitHub/GitLab/Jenkins for regression catching
  • Large community and Fortune-500 adoption signal staying power
  • Industry-standard for ML tracking
  • Weave adds LLM-native eval
  • Mature, reliable
  • Strong enterprise features
Cons
  • YAML-heavy config has a learning curve for non-engineers
  • Enterprise pricing is opaque (contact sales only)
  • Red-team scans can be slow and token-expensive at scale
  • Heavier UX than LLM-native tools
  • LLM features still catching up
Websitepromptfoo.devwandb.ai
Pick Promptfoo if
  • ✅ Genuinely open source and self-hostable, not a fake-OSS funnel
  • ✅ Model-agnostic; works across OpenAI, Anthropic, local, custom APIs
  • ✅ Red-teaming covers prompt injection, jailbreaks, PII, policy violations
  • ✅ Clean CI integration with GitHub/GitLab/Jenkins for regression catching
Pick Weights & Biases if
  • ✅ Industry-standard for ML tracking
  • ✅ Weave adds LLM-native eval
  • ✅ Mature, reliable
  • ✅ Strong enterprise features
Compare a different pair →