Braintrust vs Promptfoo
A side-by-side comparison of Braintrust and Promptfoo, two Eval tools, drawn from Ignaite's continuously-verified listings.
Compared from listings verified as of
At a glance
| Attribute | Braintrust | Promptfoo |
|---|---|---|
| Category | Eval | Eval |
| Pricing (differs) | FREEMIUM | FREE |
| License (differs) | Proprietary | Open source |
| Deployment (differs) | Cloud | — |
| Platforms (differs) | Web, API | CLI, macOS, Windows, Linux |
| Model support | BYO key / model | BYO key / model |
| Vendor (differs) | Braintrust | Promptfoo |
| Capabilities (differs) |
|
|
The honest brief
Braintrust
Eval-first: prompts are versioned objects and CI scorers block a merge when quality regresses.
- Eval workflow as the primary interface
- CI scorers block merges on regression
- Dataset versioning + OTel tracing
- Generous free tier
- Closed-source SaaS
- Self-hosting needs Enterprise contract
- Overkill for tiny single-file eval needs
Promptfoo
Define evals in plain YAML and run one goldset across models in CI — a prompt regression fails the build like any other test.
- YAML-driven, version-controllable evals
- Runs in CI, model-agnostic
- Goldsets and rubric scoring
- Also does red-teaming/security scans
- CLI-first, less of a hosted UI
- Teams may want managed dashboards
- Config sprawl on large eval suites
When to pick which
Both cover LLM evaluation.
Pick Braintrust if you need LLM observability and Prompt management.
- LLM observability (secondary capability)
- Prompt management (secondary capability)
Pick Promptfoo if you need Red-teaming and Guardrails.
- Red-teaming (primary capability)
- Guardrails (secondary capability)
They also differ on:
- Pricing
- FREEMIUM · FREE
- License
- Proprietary · Open source
- Platforms
- Web, API · CLI, macOS, Windows, Linux