Helicone vs Langfuse (2026)
Overview
Helicone is an open-source LLM observability and proxy platform. By adding a single line of code, developers get request logging, cost tracking, caching, rate limiting, and analytics for their LLM applications. Helicone supports all major LLM providers and offers both proxy and async logging modes. Popular with startups for its generous free tier and simple integration.
Langfuse is an open-source LLM engineering platform for tracing, evals, and prompt management, self-hosted or on Langfuse Cloud with a free plan.
Key features
Core capabilities each platform advertises.
- Tracing for LLM calls, tool runs, and agent steps
- Python and TypeScript SDKs plus OpenTelemetry
- LLM-as-a-judge and custom evaluations
- Datasets and experiments
- Prompt management and playground
Strengths and tradeoffs
What each tool does well, and the limitations to keep in mind.
Pros
- Open-source with 5.2K GitHub stars and strong community support
- Minimal latency overhead (under 1ms for self-hosted)
- Flexible deployment options including cloud-hosted, self-hosted, or SDK-only
- Y Combinator-backed with SOC 2 Type II and HIPAA compliance
- No code changes required for AI Gateway features like caching and rate limiting
Cons
- Adds computational cost and one network hop for cloud deployment
- Limited pricing transparency on website
- May require infrastructure expertise for self-hosted setup
Pros
- MIT-licensed core, self-hostable with Docker Compose or Kubernetes
- Tracing, evals, and prompt management in one tool
- Unlimited users on paid cloud plans
- Free Hobby plan with 50k units a month
- Native SDKs plus OpenTelemetry for other languages
Cons
- No LLM gateway, so routing, failover, and spend limits need a separate tool
- Hobby plan keeps 30 days of data and caps at 2 users
- Enterprise SSO and RBAC need the $300/month Teams add-on on Pro
- Self-hosting means running and scaling Langfuse's services yourself
Helicone or Langfuse — which should you choose?
Choose Helicone if you wantChoose if you want
Choose Langfuse if you wantChoose if you want
- Tracing and debugging LLM apps and agents
- Self-hosting LLM observability
- Versioning prompts across environments
- Scoring outputs with LLM judges and human review
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 1,000+ models through one gateway.
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