TensorZero vs Langfuse

Side-by-side comparison from the Agent Observability Index: licensing, self-hosting, pricing model and integrations — no vendor copy, primary sources linked.

TensorZeroLangfuse
One-linerOpen-source LLMOps stack unifying gateway, observability, evaluations, optimization and experimentation.Open-source (MIT) LLM engineering platform combining tracing, prompt management, evals and datasets, widely used as the default self-hosted observability stack.
CategoryObservability & TracingObservability & Tracing
Open sourceYesYes
Self-hostableYesYes
Pricing modelfreefreemium
Pricing notesFully open source (Rust gateway + ClickHouse storage)Free Hobby tier (50k units/mo); Core $29/mo, Pro $199/mo, unlimited users on paid tiers; MIT core fully self-hostable
FrameworksOpenAI SDK, Anthropic, vLLMlangchain, openai-sdk, llamaindex, litellm, opentelemetry, vercel-ai, haystack
Funding / ownership$7.3M seed (2025)YC W23; $4M seed (Lightspeed, La Famiglia)

How to choose

Sources: TensorZero · Langfuse