Langfuse vs promptfoo
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
promptfoo
Test, evaluate, and red-team LLM applications
| Feature | Langfuse | promptfoo |
|---|---|---|
| Deploy effort | Under-an-hour setup | Read-the-docs project |
| Health score | 98 · Excellent | 97 · Excellent |
| Category | Self-Hosted AI | Self-Hosted AI |
| License | MIT | MIT |
| Language | TypeScript | TypeScript |
| Setup difficulty | Medium | Easy |
| Min. RAM | 2,048 MB | 1,024 MB |
| Deployment | docker, kubernetes, helm | bare-metal, binary, source |
| GitHub stars | ★ 34,989 | ★ 25,409 |
| First released | 2023 | 2023 |
| Replaces | LangSmith | LangSmith |
What are Langfuse and promptfoo?
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
promptfoo
promptfoo is a developer-friendly tool for testing and evaluating prompts, models, and RAG systems. It supports automated evaluations, comparisons, and security red-teaming with a local web viewer.
- Automated prompt evals
- Model comparison matrix
- Red-teaming and security tests
- Local web viewer
Langfuse vs promptfoo: key differences
Both projects are written in TypeScript. Promptfoo is the lighter option, starting around 1,024 MB of RAM against 2,048 MB for Langfuse. Langfuse lists first-class Docker deployment; promptfoo 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 promptfoo if…
- Simple YAML configs
- Red-teaming built in
- Runs fully locally
Watch out for
- CLI-centric workflow
- Node.js required
Frequently asked questions
Is Langfuse or promptfoo better?
Neither is universally better. Langfuse has the larger community, while promptfoo is simpler to set up (easy difficulty). Choose based on the comparison table above and your own setup.
Are Langfuse and promptfoo free and open-source?
Yes. Langfuse is licensed under MIT and promptfoo under MIT. Both can be self-hosted at no software cost.
Can I run Langfuse and promptfoo with Docker?
Langfuse: yes. promptfoo: check the project docs for container support.
Which is lighter on resources, Langfuse or promptfoo?
promptfoo 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.