Provisional comparison

Langfuse vs Promptfoo

Langfuse is provisional S-tier and Promptfoo is provisional A-tier on Agent Observability & Evals. Rankings are never for sale.

Langfuse

Open-source agent tracing, evals and prompt management.

Open-source testing and red-teaming for prompts, agents and RAG.

Field	Langfuse	Promptfoo
Tier	S · provisional	A · provisional
Why	Leading open-source observability (35k+ stars), self-hostable.	Go-to open-source eval and red-team CLI (26k+ stars).
Pricing	open-source / freemium cloud · starts at $29/mo	open-source / enterprise
GitHub stars	35,875	26,019
Last push	Oct 15, 2026	Oct 15, 2026
Last verified	Oct 15, 2026	Oct 15, 2026