Braintrust vs Inspect AI
A side-by-side comparison of Braintrust and Inspect AI, two Eval tools, drawn from Ignaite's continuously-verified listings.
Compared from listings verified as of
At a glance
| Attribute | Braintrust | Inspect AI |
|---|---|---|
| Category | Eval | Eval |
| Pricing (differs) | FREEMIUM | FREE |
| License (differs) | Proprietary | Open source |
| Deployment (differs) | Cloud | — |
| Platforms (differs) | Web, API | CLI, API |
| Model support | BYO key / model | BYO key / model |
| Vendor (differs) | Braintrust | UK AI Security Institute |
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
Inspect AI
Built by the UK AI Security Institute and adopted by Anthropic, DeepMind, METR, and Apollo as a shared eval framework; MIT.
- Adopted across major safety labs
- Composable datasets/solvers/scorers
- 200+ prebuilt evals (inspect_evals)
- Sandboxed tool + multi-turn agent runs
- MIT-licensed, provider-agnostic
- Python/code framework, not a UI product
- Steeper than no-code eval tools
- You wire up your own model keys