Compare Helicone and Langfuse side by side. Both are tools in the Observability, Prompts & Evals category.
Choose Helicone if open-source with 5.2K GitHub stars and strong community support.
Choose Langfuse if fully open-source with MIT license and free for commercial use with no usage limits.
Want to compare Helicone and Langfuse on your own traffic?
Respan lets you trace LLM and agent calls across any model or framework, A/B test prompts on production traffic, and route requests across 250+ models through one gateway. Free tier covers 10K traces per month. Setup in 5 minutes, no credit card.
| Category | Observability, Prompts & Evals | Observability, Prompts & Evals |
| Pricing | — | Open Source |
| Best For | — | Teams who want open-source LLM observability they can self-host and customize |
| Website | helicone.ai | langfuse.com |
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Helicone is an open-source AI Gateway and LLM Observability platform that enables developers to route, debug, and analyze their AI applications with end-to-end visibility from user sessions to individual token decisions. As a Y Combinator-backed company, Helicone combines observability with infrastructure management, offering token-level cost analysis, prompt version tracking, and session tracing alongside intelligent routing features like caching, rate limiting, and load balancing. The platform provides real-time dashboards, user metrics tracking, alert systems, and multi-step LLM interaction visualization for root cause analysis. Helicone is SOC 2 Type II certified, HIPAA compliant, and offers flexible deployment options including cloud-hosted gateway leveraging Cloudflare's global network, self-hosted via Kubernetes Helm charts, or SDK-only observability without proxying.
Langfuse is an open-source LLM engineering platform that provides comprehensive tools for traces, evaluations, prompt management, and metrics to debug and improve LLM applications. Founded in Berlin, Germany in 2022, Langfuse quickly became a leading platform in the LLM observability space. The platform features MIT-licensed open-source core with no usage limits for commercial use, making it highly accessible to teams of all sizes. Langfuse offers deep integration with popular frameworks including LangChain, OpenAI, LlamaIndex, and LiteLLM. The platform provides detailed tracing capabilities, evaluation tools, comprehensive prompt management, and rich metrics tracking. In January 2026, Langfuse was acquired by ClickHouse, Inc., marking a significant transatlantic venture exit and validating the platform's technology and market position. The acquisition demonstrates the value of Langfuse's approach to LLM observability, evaluations, and prompt management.
Tools for monitoring LLM applications in production, managing and versioning prompts, and evaluating model outputs. Includes tracing, logging, cost tracking, prompt engineering platforms, automated evaluation frameworks, and human annotation workflows.
Browse all Observability, Prompts & Evalstools →One platform for routing, observability, tracing, and evals across every LLM provider.