Braintrust
Connect production traces to evaluation datasets while separating data processing, scoring and model inference costs.
- Starting price
- Pro USD 249/month
- Free access
- Starter: 1 GB and 10k scores
- Billing unit
- Data, scores and model tokens
- Platform
- Hosted developer platform
- Verified
- 26 Oct 2026
Overview
What you provide
- Send application traces and a labeled evaluation dataset with expected behavior or scoring criteria.
What you get
- The platform provides trace inspection, experiment comparisons and evaluation scores for reviewing AI behavior.
Choosing this tool
Braintrust is useful when failures found in production must become repeatable evaluation cases. Its unlimited users do not remove data or score charges. Compare PromptLayer for prompt version workflows and request transactions, or LangSmith for per-seat observability and agent deployment. Pick the billing unit that matches the workload you actually instrument.
A decision worked through
On Starter, 3 GB of processed data and 20,000 scores imply (3 - 1) × USD 4 + (20,000 - 10,000) / 1,000 × USD 2.50 = USD 33 in those two overages. This excludes model calls beyond credits. A larger workload does not automatically make the USD 249 Pro fee economical; retention and access controls may be the deciding features.
Braintrust alternatives for ai tracing and evaluation
Compare Braintrust with PromptLayer, LangSmith for ai tracing and evaluation. Compare the published operating scope as well as the billing unit.
| Product | Price / unit | Free allowance | Input → output | Key limit |
|---|---|---|---|---|
| BraintrustRead profileOfficial source ↗ | Pro USD 249/mo plus usage | 1 GB; 10k scores monthly | Traces become scored experiments. | Starter retention is 14 days. |
| PromptLayerRead profileOfficial source ↗ | Pro USD 49/mo plus transactions | Five users; one workspace | Prompts become versioned tests. | Pro keeps 2,500 included requests. |
| LangSmithRead profileOfficial source ↗ | Plus USD 39/seat/mo plus usage | 5k base traces and one seat | Agent runs become inspected traces. | Plus includes 10k traces total. |
Setup & workflow
- Capture a small representative trace set.
- Run evaluators against known good and bad cases.
- Promote reviewed failures into a regression dataset.
Requirements & installation
- Instrument one application and prepare representative passing and failing cases before choosing a score budget.
Limits & review
- An automated score is only as useful as its rubric and examples. Fourteen-day Starter retention may be too short for a monthly incident review, and included model credits are not unrestricted inference.
Your part
- Check whether evaluators catch real failures and protect sensitive content before including production traces.
Sources & verification5
This profile is based on official sources, not a hands-on product test.
Vendor descriptions and demos document advertised features. Editorial guidance is based on these sources.
- Braintrust official pricingbraintrust.dev
- Braintrust official productbraintrust.dev
- Braintrust official referencebraintrust.dev
- PromptLayer official referencepromptlayer.com
- LangSmith official referencewww.langchain.com
