· Observability & evals/ Head to head

Langfuse vs Braintrust

Langfuse is open source and Braintrust is not, so the question is whether you want source access and the option to fork, or would rather have a vendor accountable for it.

Langfuse

Open-source tracing, prompt management and evals. Self-hostable in one compose file.

Open source · freemium · can be self-hosted · SDKs for Python and TypeScript

Braintrust

Eval-first platform — scorers, datasets and a playground for prompt iteration.

Proprietary · freemium · can be self-hosted · SDKs for Python and TypeScript

· Side by side/ 3 of 6 differ
LangfuseBraintrust
LicenceOpen sourceProprietary
Pricingfreemiumfreemium
Self-hostableYesYes
LanguagesPython, TypeScriptPython, TypeScript
Installpip install langfuse
Keys requiredLANGFUSE_PUBLIC_KEY, LANGFUSE_SECRET_KEYBRAINTRUST_API_KEY
· Common questions/ FAQ

What is the difference between Langfuse and Braintrust?

Langfuse is open source and Braintrust is not, so the question is whether you want source access and the option to fork, or would rather have a vendor accountable for it. Langfuse: Open-source tracing, prompt management and evals. Self-hostable in one compose file. Braintrust: Eval-first platform — scorers, datasets and a playground for prompt iteration.

Can Langfuse and Braintrust be self-hosted?

Langfuse can run on your own infrastructure. Braintrust can run on your own infrastructure.

Are Langfuse and Braintrust open source?

Langfuse is open source (freemium). Braintrust is proprietary (freemium).

Build a stack with LangfuseAll observability & evals options
· For agents/ This page, machine-readable

Every page here answers to Accept: text/markdown and returns the same content at roughly a tenth the tokens. No separate site, no toggle — same URL.

curl -s -H "Accept: text/markdown" https://newagent.build/compare/langfuse-vs-braintrust