Back to all tools
Free-Limited
Tool Comparison
Weights & Biases
The ML experiment tracking and LLM observability platform used by top AI teams.
VS
At a Glance
| Attribute | Weights & Biases | LangSmith |
|---|---|---|
| License / Pricing | Free-Limited | Free-Limited |
| Type | ai | ai |
| GitHub Stars | — | — |
| Rating | 4.7/5 | 4.5/5 |
| Key Features | 6 listed | 6 listed |
| Integrations | 5 listed | 5 listed |
| Categories | MLOpsAI Observability | AI Observability |
Key Features
Weights & Biases
- Automatic experiment tracking with one line of code
- Sweeps for automated hyperparameter optimization
- Artifacts for dataset and model versioning
- W&B Tables for visualizing model predictions
- Weave for LLM tracing, evaluation, and monitoring
- Reports for shareable ML research documentation
LangSmith
- Full trace visualization for every LLM call and chain step
- Dataset management for evaluation benchmarks
- Automated evaluators with LLM-as-judge
- Prompt versioning and A/B testing
- Production monitoring with latency and error tracking
- Human annotation workflows for labeling
Real-World Use Cases
Weights & Biases
Hyperparameter sweep across GPU cluster
Define a sweep config with parameter search space
LangSmith
Debug a hallucinating RAG pipeline
Add LANGSMITH_API_KEY to your environment
Integrations
Weights & Biases
mlflowhuggingfacekubeflowpytorchtensorflow
LangSmith
langchainllamaindexopenaianthropicpinecone
🏆 Which should you choose?
Choose Weights & Biases if…
- → you're already in the MLOps ecosystem and prefer Weights & Biases's workflow
Choose LangSmith if…
- → you're already in the AI Observability ecosystem and prefer LangSmith's workflow