head to head · open source
Langfuse vs LangWatch
Langfuse has 36,970 GitHub stars, 4,150 forks, 926 open issues and last shipped yesterday. LangWatch has 5,011 stars, 425 forks, 939 open issues and last shipped yesterday. Langfuse leads on adoption by 638% (36,970 vs 5,011 stars). Langfuse is written in TypeScript under a custom or non-standard licence; LangWatch is written in TypeScript under Apache-2.0. Langfuse has attracted 11% as many forks as stars, LangWatch 8%. LangWatch was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 5 topic tags (analytics, evaluation, llm, llmops), so they are genuine substitutes rather than adjacent tools.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Langfuse | LangWatch | |
|---|---|---|
| GitHub stars | ★ 37K | ★ 5.0K |
| License | Custom / other | Apache-2.0 |
| Written in | TypeScript | TypeScript |
| Last push | 2026-11-04 | 2026-11-04 |
| Forks | ⑂ 4.2K | ⑂ 425 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Langfuse if
- You weight community size — 37K stars and counting
- You want the Custom / other license terms
- Your stack matches TypeScript
- You value the larger contributor base for long-term maintenance
pick LangWatch if
- You want the LangWatch feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches TypeScript
- You evaluated both and LangWatch fits your workflow better
About Langfuse
Langfuse Cloud · Self Host · Demo Docs · Report Bug · Feature Request · Changelog · Roadmap · Langfuse is an open source LLM engineering platform. It helps teams collaboratively develop, monitor, evaluate, and debug AI applications. Langfuse can be self hosted in minutes and is battle tested . Proudly made with ClickHouse open source database. 🧑💻 We're hiring Langfuse is growing fast (we doubled the team in the last 6 months) since January 2026 we're part of ClickHouse, we're hiring engineering hybrid across the EU. We hire engineers who love open source and great developer experiences. See open roles → ✨…
read the full Langfuse overview →
About LangWatch
Website · Docs · Discord · Self hosting Why LangWatch? The platform for LLM evaluations and AI agent testing. We help teams test, simulate, evaluate, and monitor LLM powered agents end to end — before release and in production. Built for teams that need regression testing, simulations, and production observability without building custom tooling. End to end agent simulations Run realistic scenarios against your full stack (tools, state, user simulator, judge) and pinpoint where your agents break, and why? down to each decision. Eval + observability + prompts in one loop Trace → dataset → evaluate → optimize…
read the full LangWatch overview →
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Frequently asked questions
Is Langfuse or LangWatch more popular?
Langfuse has 36,970 GitHub stars and LangWatch has 5,011. Langfuse has the larger community by that measure.
Are Langfuse and LangWatch free?
Both are open source. Langfuse has no licence declared in this registry, and LangWatch is licensed under Apache-2.0. Both are free to self-host.
What is the difference between Langfuse and LangWatch?
Langfuse is written in TypeScript and LangWatch in TypeScript. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Langfuse or LangWatch?
Choose Langfuse if you want the larger community (36,970 stars) or its Custom / other licence terms. Choose LangWatch if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.