Langfuse vs OpenLLMetry
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
OpenLLMetry
Open-source observability for LLM applications
| Feature | Langfuse | OpenLLMetry |
|---|---|---|
| Deploy effort | Under-an-hour setup | Under-an-hour setup |
| Health score | 98 · Excellent | 91 · Excellent |
| Category | Self-Hosted AI | Self-Hosted AI |
| License | MIT | Apache-2.0 |
| Language | TypeScript | Python |
| Setup difficulty | Medium | Medium |
| Min. RAM | 2,048 MB | 512 MB |
| Deployment | docker, kubernetes, helm | docker, source |
| GitHub stars | ★ 34,989 | ★ 7,445 |
| First released | 2023 | 2023 |
| Replaces | LangSmith | LangSmith, Datadog LLM Observability |
What are Langfuse and OpenLLMetry?
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
OpenLLMetry
OpenLLMetry is a set of OpenTelemetry extensions from Traceloop that add observability to LLM applications. It instruments calls to model providers and vector databases so traces and metrics can be sent to any self-hosted backend.
- OpenTelemetry-based tracing
- Instruments popular LLM SDKs
- Vendor-neutral export
- Vector database instrumentation
Langfuse vs OpenLLMetry: key differences
Langfuse is written in TypeScript, while OpenLLMetry is built with Python. Licensing differs — MIT for Langfuse versus Apache-2.0 for OpenLLMetry. OpenLLMetry is the lighter option, starting around 512 MB of RAM against 2,048 MB for Langfuse. Langfuse has the considerably larger community, at 34,989 GitHub stars versus 7,445.
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 OpenLLMetry if…
- Released under the Apache-2.0 license
- First-class Docker support for quick deployment
- Mature project with 7.4k GitHub stars
- Written in Python
Frequently asked questions
Is Langfuse or OpenLLMetry 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 OpenLLMetry free and open-source?
Yes. Langfuse is licensed under MIT and OpenLLMetry under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Langfuse and OpenLLMetry with Docker?
Langfuse: yes. OpenLLMetry: yes.
Which is lighter on resources, Langfuse or OpenLLMetry?
OpenLLMetry has the smaller minimum footprint at 512 MB of RAM, compared to about 2,048 MB for Langfuse. Real-world usage depends on library size, user count, and enabled features.