Langfuse
Evaluation & observability · Open source
About
An open-source LLM engineering platform for tracing, prompt management, evaluations and cost tracking.
Key features
- Traces and spans for LLM calls
- Prompt management with versions
- Evals and datasets
- Cost and latency dashboards
Best for
- — Tracing LLM apps in production
- — Self-hosted prompt management
- Pricing
- Open source
- Platforms
- Web, Self-hosted, API
- Works with
- LangChain, OpenAI, LlamaIndex
- Last checked
- 2026-10-29
- Status
- Listed, not yet tested
Our take
A popular, well-documented default for observability. Self-hosting at scale needs some operational effort.
Features and pricing change often — confirm on langfuse.com before you commit.
Alternatives to Langfuse
| Tool | Type | Pricing | Best for |
|---|---|---|---|
| Langfuse (this) | Evaluation & observability | Open source | Tracing LLM apps in production |
| LangSmith | Evaluation & observability | Freemium | LangChain and LangGraph users |
| Braintrust | Evaluation & observability | Freemium | Systematic evals before shipping |
| Arize Phoenix | Evaluation & observability | Open source | Local debugging of LLM traces |
| W&B Weave | Evaluation & observability | Freemium | Teams already on Weights & Biases |
| Helicone | Evaluation & observability | Freemium | Quick cost and usage visibility |
| promptfoo | Evaluation & observability | Open source | Prompt regression tests in CI |