Langfuse

7.8AI-Powered

Open-source LLM observability and engineering platform.

Understand Your Numbers

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What It Does

Traces every LLM call and agent workflow with native SDKs
Tracks token usage, costs, latency, and user feedback
Manages prompt versions with playground and A/B experiments
Automated and human evaluations with LLM-as-a-judge and custom metrics

Strengths & Weaknesses

Strengths

+Open-source (MIT) with free self-hosting
+Free cloud plan with 50,000 observations/month
+Framework-agnostic — works with LangChain, LlamaIndex, OpenAI SDK
+SOC 2 and HIPAA compliance on Pro plan

Weaknesses

−Observation unit pricing can be hard to predict
−

AI Features

LLM-as-a-judge evaluations, AI-assisted prompt optimization, and deep observability into AI agent and LLM call behavior in production.

STOA's Verdict

One of the best tools for understanding what your AI application does in production. Open-source, generous free tier, framework-agnostic. If building LLM products and tracking performance and quality, Langfuse belongs on your shortlist.

Generate Your Own Learning Materials

Coming Soon

AI-generated training guides tailored to your team's size, skill level, and focus areas for Langfuse — coming in v0.3.2.

View our roadmap →

User Reviews

Reviews coming soon

We're building a review system so business owners like you can share real experiences with Langfuse.

Langfuse

What It Does

Strengths & Weaknesses

Strengths

Weaknesses

Integrations

AI Features

STOA's Verdict

Generate Your Own Learning Materials

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