Langfuse vs Ragas
A side-by-side comparison of two self-hosted self-hosted ai options — licensing, setup difficulty, resource needs, and what each one replaces.
Langfuse
Open-source observability and analytics for LLM apps
VS
Ragas
Evaluation framework for retrieval-augmented generation
| Feature | Langfuse | Ragas |
|---|---|---|
| Deploy effort | Under-an-hour setup | Read-the-docs project |
| Health score | 98 · Excellent | 72 · Good |
| Category | Self-Hosted AI | Self-Hosted AI |
| License | MIT | Apache-2.0 |
| Language | TypeScript | Python |
| Setup difficulty | Medium | Medium |
| Min. RAM | 2,048 MB | 1,024 MB |
| Deployment | docker, kubernetes, helm | source |
| GitHub stars | ★ 34,989 | ★ 15,834 |
| First released | 2023 | 2023 |
| Replaces | LangSmith | LangSmith |
What are Langfuse and Ragas?
Langfuse
Langfuse is an open-source platform for tracing, evaluating, and monitoring LLM applications. It captures detailed traces, manages prompts, and provides analytics dashboards for production AI systems.
- LLM tracing and analytics
- Prompt management
- Evaluation tooling
- Self-hostable
Ragas
Ragas is an open-source framework for evaluating retrieval-augmented generation pipelines. It provides metrics for faithfulness, answer relevancy, and context precision that can be run entirely on self-hosted infrastructure.
- RAG-specific metrics
- Synthetic test set generation
- Framework agnostic
- Local evaluation
Langfuse vs Ragas: key differences
Langfuse is written in TypeScript, while Ragas is built with Python. Licensing differs — MIT for Langfuse versus Apache-2.0 for Ragas. Ragas is the lighter option, starting around 1,024 MB of RAM against 2,048 MB for Langfuse. Langfuse has the considerably larger community, at 34,989 GitHub stars versus 15,834. Langfuse lists first-class Docker deployment; Ragas does not.
Why pick each one
Choose Langfuse if…
- Detailed LLM tracing
- Prompt management built in
- Many SDK integrations
Watch out for
- ClickHouse and Redis required
- Some features enterprise
Choose Ragas if…
- Research-backed metrics
- Simple Python API
- Framework integrations
Watch out for
- Metrics need LLM calls
- Frequent API changes
Frequently asked questions
Is Langfuse or Ragas better?
Neither is universally better. Langfuse has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.
Are Langfuse and Ragas free and open-source?
Yes. Langfuse is licensed under MIT and Ragas under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Langfuse and Ragas with Docker?
Langfuse: yes. Ragas: check the project docs for container support.
Which is lighter on resources, Langfuse or Ragas?
Ragas has the smaller minimum footprint at 1,024 MB of RAM, compared to about 2,048 MB for Langfuse. Real-world usage depends on library size, user count, and enabled features.