Braintrust vs Promptfoo

Braintrust is freemium — a usable free tier with paid plans above it. Promptfoo is freemium — a usable free tier with paid plans above it. Both are listed under LLM Eval & Observability, so this is a like-for-like comparison. Neither is ranked above the other — Flocci carries no sponsored placement.

Braintrust vs Promptfoo — straight answers

Braintrust vs Promptfoo: what is the difference?

Braintrust is freemium — a usable free tier with paid plans above it and is listed for free Starter plan ships model credits and scored evals with no card required. Promptfoo is freemium — a usable free tier with paid plans above it and is listed for open-source CLI/library for evaluating prompts, models and RAG pipelines side by side, runs in CI. Both sit in LLM Eval & Observability.

Is Braintrust or Promptfoo cheaper to start with?

Neither — Braintrust and Promptfoo are both freemium, so the choice comes down to capability rather than cost. Both entries list what they uniquely do above.

Which should I choose, Braintrust or Promptfoo?

Choose Braintrust if you need free Starter plan ships model credits and scored evals with no card required; choose Promptfoo if you need open-source CLI/library for evaluating prompts, models and RAG pipelines side by side, runs in CI. Flocci AI Tools does not rank one above the other — it shows both feature sets side by side and lets the requirement decide.

Braintrust compared with Promptfoo: pricing tier, category, listed capabilities and links.
 BraintrustPromptfoo
Pricing tierFree tier + paid plansFree tier + paid plans
Free to startYesYes
CategoryAI Models & Local ExecutionAI Models & Local Execution
TypeLLM Eval & ObservabilityLLM Eval & Observability
Listed capabilities
  • Free Starter plan ships model credits and scored evals with no card required
  • Unlimited users/projects/datasets/playgrounds even on the free tier
  • Built-in playground for side-by-side prompt/model comparison against production traces
  • Open-source CLI/library for evaluating prompts, models and RAG pipelines side by side, runs in CI
  • Automated red-teaming to surface prompt injection, jailbreak and data-leak vulnerabilities
  • 300,000+ user community with an enterprise tier for teams needing hosted guardrails
Tagsbraintrust, llm eval platform, prompt playground, ai evaluation, free tier, scoringpromptfoo, prompt testing, llm red teaming, eval framework, open source, free, ci for prompts
Websitebraintrust.devpromptfoo.dev
Full pageBraintrust details →Promptfoo details →
AlternativesBraintrust alternatives →Promptfoo alternatives →

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