A agentindex
Comparison

Braintrust vs Langfuse

A like-for-like, spec-level comparison. Both entries are verified against their docs and repo.

Braintrust

Evals and prompt playground for serious teams.

  • + Excellent eval and scoring UX
  • + Strong for prompt-engineering-heavy teams
  • − Proprietary platform
  • − Self-host story limited

Langfuse

The most-used open-source LLM observability tool.

  • + Open source and self-hostable
  • + Framework-agnostic via OpenTelemetry
  • − Self-hosting ClickHouse is operational work
  • − Eval features trail dedicated eval tools
Spec Braintrust Langfuse
Category eval-observability eval-observability
License Proprietary MIT
Open source No Yes
Self-hostable No Yes
MCP support No No
Pricing freemium freemium
Starting price Free tier Self-host free; cloud tier
Models multi multi
Languages python, typescript python, typescript
GitHub stars — 29.8k
Last activity — 2026-06-25